Epoxy tile grout is a 100 % solids joint filler of epoxy resin, amine hardener and silica or color-coated quartz filler that cures to a dense, non-porous thermoset, specified by ANSI A118.3-2021 (R2025) and as EN reaction resin grout RG. It hardens by chemical reaction rather than by cement hydration, so the cured joint needs no sealer and resists stains, water, food acids and cleaning chemicals.
ANSI A118.3-2021 (R2025) sets the US minimums: compressive strength above 24.1 MPa (3,500 psi), tensile strength and quarry tile shear bond above 6.90 MPa (1,000 psi) and shrinkage below 0.25 %. The compressive minimum sits above the 20.7 MPa (3,000 psi) that ANSI A118.7-2019 asks of a high performance cement grout, and cost follows the same order, with epoxy ranked highest among the ANSI grout classes. Epoxy tile grout is one tile product class in this reference to construction chemicals.
This page follows the order of a specification: identity and names, cure chemistry, uses, the six A118.3 properties, the ANSI and EN class systems, selection, joint preparation, coverage and cure by temperature, failures, safety and VOC rules, dated costs, alternatives including furan grout, and sourcing.
Standards, codes and regulations are checked against their issuing bodies, product values against the named data sheet and prices against the dated source named in the sentence; see our methodology and fact-checking.
The summary table below lists the attributes a specifier checks first on an epoxy tile grout.
| Attribute | Value |
|---|---|
| Chemistry | Epoxy resin + amine hardener + silica or color-coated quartz filler, 100 % solids |
| Forms | Three-part kit (resin, hardener, filler powder); pre-filled two-component pack |
| US standard | ANSI A118.3-2021 (R2025), chemical resistant, water cleanable tile-setting and tile-grouting epoxy |
| EU and international class | Reaction resin grout RG (EN 13888-1:2022, ISO 13007-3:2010) |
| Installation standards | ANSI A108.6-2023 (installation of epoxy); ANSI A108.10-2026 (installation of grout in tilework) |
| Joint width (product value) | 1.6 to 12.7 mm (1/16 to 1/2 in), SpectraLock PRO Premium (DS-681) |
| Substrate window (product value) | 16 to 32 °C (60 to 90 °F) for 72 hours, Kerapoxy CQ (TDS 2026-05-04) |
| Hazards | Skin-sensitizing resin and amine hardener; quartz dust from the filler powder |
What Is Epoxy Tile Grout?#
Epoxy tile grout fills the joints between ceramic, porcelain, glass and stone tiles with a reactive resin instead of cement, so it hardens by chemical cure rather than hydration and needs no sealer afterwards. The resin side and the hardener side react once mixed, and the filler gives the joint its body and its color. Cement grout, by contrast, stays porous after hydration and needs a sealer for stain resistance.
Epoxy tile grout is one product class with its own US standard, ANSI A118.3, and its own European class, RG. It is not epoxy machinery grout, the flowable, high-strength product placed under equipment bases, even though both carry the word epoxy in their names. Within the tile family it sits next to cement grouts, premixed grouts, adhesives and membranes, all covered under tile adhesives and tile installation systems.
Resin, hardener and filler: two-part and three-part epoxy grouts#
Epoxy grouts are sold in two forms: a two-component liquid with a separate filler powder (three-part kits) and a pre-filled two-component pack. The three components that make up every epoxy grout are listed below.
- Epoxy resin (Part A): the liquid binder that cross-links with the hardener; resin chemistry is covered under epoxy resins and hardeners.
- Amine hardener (Part B): the curing agent whose reaction with the resin turns the liquid mix into a thermoset joint.
- Filler (Part C, or pre-blended in two-component packs): silica or color-coated quartz, where the coated quartz carries the grout color.
ANSI A118.3-2021 (R2025) covers setting epoxies as well as grouting epoxies, so one product can bed the tile and fill the joint. Kerapoxy CQ used as a setting epoxy covers 1.67 m² per 3.79 L (18 ft² per US gal) with a 6.4 mm (1/4 in) square notch, according to its data sheet dated 2026-05-04.
Regional names: reaction resin grout RG and A118.3 grouting epoxy#
Epoxy grout carries three formal names that point to its standard, not to a brand. The table below lists each name with the region that uses it and what it means.
| Name | Region | Meaning |
|---|---|---|
| Reaction resin grout, class RG | EU (EN 13888-1:2022), international (ISO 13007-3:2010) | The resin-bound grout class beside the cement classes CG1 and CG2 |
| Chemical resistant, water cleanable tile-grouting epoxy | US (ANSI A118.3-2021 (R2025)) | The A118.3 scope name, which also covers setting epoxy |
| 100 % solids epoxy grout | Trade usage | Names the fully reactive, 100 % solids chemistry |
| Epoxy grout | India | Common name in a high-demand market |
| Not this product: epoxy machinery grouts | All regions | Equipment bases, tested under ASTM C579-23 |
Every name on this page is written in full, because epoxy machinery grout shares the same short forms and belongs to a different product class with a different standard.
How Does Epoxy Grout Cure and Resist Stains?#
Epoxy grout cures by an amine-epoxy polyaddition reaction that links resin and hardener into a dense, non-porous thermoset, which is why it resists stains and needs no sealer, while cement grout stays porous. In a polyaddition, resin and hardener molecules join directly, so the mixed material becomes the hardened joint with no water to evaporate, the reason the product is sold as 100 % solids. Porosity decides stain resistance: a cement grout keeps an open pore system after hydration and draws liquids in unless it is sealed, while the cured epoxy joint offers no open path for them.
Water cleanability and stain resistance arrive at different times. Fresh epoxy grout is water-cleanable only within its working time, and once that window closes, residue left on the tile face hardens into haze. Stain resistance builds over days after grouting: SpectraLock PRO Premium reaches it 7 days after grouting at 21 °C (70 °F) according to its data sheet (DS-681), and acids that reach the joint before a 7-day cure can stain it. ANSI A118.3-2021 (R2025) frames the same timing as requirements: an initial set later than 2 hours, service within 7 days and water cleanability tested at 80 minutes.
Where Is Epoxy Grout Used?#
Epoxy grout is used where joints face water, food, cleaning chemicals or heavy traffic: showers and wet rooms, commercial kitchens and food areas, swimming pools and steam rooms, laboratories and floors that see chemical spills. Those settings share one need, a joint that stays clean and intact under liquids that would soak into an unsealed cement grout. The five uses and joint limits are listed below.
- Showers, bathrooms and wet rooms: stain-free joints without a sealer, laid over a membrane that does the waterproofing.
- Commercial kitchens and food areas: stain-prone floors where food acids and cleaning chemicals reach the joints; stain-proof grout maps to class RG and ANSI A118.3.
- Swimming pools and steam rooms: immersed joints that need a full cure before filling, set over the shell test and membrane described under swimming pool waterproofing and tanking.
- Laboratories and chemical spill floors: chemical exposure maps to RG and ANSI A118.3, with ANSI A118.5 furan grout for harsh chemicals.
- Joint widths of 1.6 to 12.7 mm (1/16 to 1/2 in): the range of SpectraLock PRO Premium (DS-681), while Kerapoxy CQ stays non-sag in wall joints up to 10 mm (3/8 in) (TDS 2026-05-04).
Ceramic, porcelain, glass and stone tiles all take epoxy grout. Soft polished marble, glass and white porous stone carry one condition: a test on a spare tile first, because the quartz filler can scratch them and the resin can stain them.
Epoxy grout in showers, bathrooms and wet rooms#
In showers and bathrooms epoxy grout keeps joints free of staining and needs no sealer, but it does not waterproof the floor or walls. SpectraLock PRO Premium's data sheet (DS-681) states that the grout "is not a replacement for a waterproofing membrane" and sets 10 days at 21 °C (70 °F) before pool or steam-room immersion. The same limit applies across the tile assembly, since paint, plaster, tile and grout are not waterproofing membranes.
Water management in a shower therefore sits below the tile. A bonded membrane carries the water load, the adhesive bed bonds the tile with at least 95 % mortar contact in wet areas and exteriors (ANSI A108.5-2023 practice, against at least 80 % in dry interior areas), and the epoxy grout seals the joint surface against stains. Questions about waterproof grout and waterproofing grout are answered under tile waterproofing membranes.
Which Properties Define Epoxy Grout Performance?#
Six properties define an epoxy grout under ANSI A118.3-2021 (R2025): bond to quarry tile, compressive and tensile strength, thermal shock resistance, shrinkage and setting behavior, including how long the mix stays water-cleanable. Each property has a section number in the standard, and a data sheet reports its test result against that number. The table below lists the six properties, the A118.3 section and requirement, and what each one protects in service.
| Property | Test (A118.3 section) and requirement | Why it matters |
|---|---|---|
| Quarry tile shear bond | 5.5: more than 6.90 MPa (1,000 psi) | Holds the joint edges to the tile |
| Compressive strength | 5.6: more than 24.1 MPa (3,500 psi) | Carries traffic and point loads in the joint |
| Tensile strength | 5.7: more than 6.90 MPa (1,000 psi) | Resists cracking when the joint is pulled |
| Thermal shock | 5.8: more than 3.45 MPa (500 psi) | Keeps the bond through hot and cold cycles |
| Shrinkage | 5.3: less than 0.25 % | Limits gaps at the joint edges |
| Setting | 5.1, 5.2: initial set more than 2 h, service less than 7 days, water cleanability at 80 min | Sets the working and cleaning window |
Service temperature is not one of the six sections; it is a product value, and Kerapoxy CQ lists service up to 100 °C (212 °F) on its data sheet dated 2026-05-04.
Standard requirement or product value: reading an epoxy grout data sheet#
A requirement is the minimum every A118.3 grouting epoxy must reach in the named test; a data-sheet value is what one product reached. SpectraLock PRO Premium reports 26.2 MPa (3,800 psi) compressive and 7.6 MPa (1,100 psi) tensile strength at 7 days and 0.10 % shrinkage under A118.3 sections 5.6, 5.7 and 5.3 (DS-681), against minimums of 24.1 MPa (3,500 psi), 6.90 MPa (1,000 psi) and 0.25 %. A margin above a minimum is not a higher class, because A118.3 sets one pass level per property and a grout either meets the section or does not. A data sheet that prints results without the requirement column leaves the reader to check each section against the table above.
Which Standards Classify Epoxy Grout: ANSI A118.3 and EN 13888 Class RG?#
Epoxy tile grout is classified by ANSI A118.3-2021, reaffirmed in 2025, in the US and by class RG of EN 13888-1:2022 and ISO 13007-3:2010 in Europe and internationally, and the two systems use different tests. Installation has its own documents: ANSI A108.6-2023 covers the installation of epoxy and has an open project initiation notice (PINS), and ANSI A108.10-2026 covers the installation of grout in tilework. The table below sets the US requirements beside the European class and lists the status of each document.
| Property | ANSI A118.3-2021 (R2025) requirement (section) | EN 13888-1:2022 / ISO 13007-3:2010 class RG |
|---|---|---|
| Quarry tile shear bond | More than 6.90 MPa (1,000 psi) (5.5) | Not an RG property |
| Compressive strength | More than 24.1 MPa (3,500 psi) (5.6) | Declared value on the data sheet, tested to EN 13888-2:2022 |
| Tensile strength | More than 6.90 MPa (1,000 psi) (5.7) | Not an RG property |
| Thermal shock | More than 3.45 MPa (500 psi) (5.8) | Not an RG property |
| Shrinkage | Less than 0.25 % (5.3) | Declared value on the data sheet, tested to EN 13888-2:2022 |
| Setting and cleanability | Initial set more than 2 h, service less than 7 days, cleanable at 80 min (5.1, 5.2) | Not an RG property |
| Status | Current (TCNA standards status, 2026-09-10) | EN 13888-1:2022 published 2022-09-13; ISO 13007-3:2010 confirmed 2025 |
The full US series for tile mortars, grouts and membranes, is set out under ANSI A118 and A136 tile standards.
ANSI A118.3-2021 requirements for grouting epoxies#
ANSI A118.3-2021 (R2025) requires a grouting epoxy to exceed 6.90 MPa (1,000 psi) quarry shear bond, 24.1 MPa (3,500 psi) compressive strength and 6.90 MPa (1,000 psi) tensile strength, with shrinkage under 0.25 %. The standard covers chemical resistant, water cleanable tile-setting and tile-grouting epoxy, and the TCNA standards status page of 2026-09-10 lists the 2021 edition, reaffirmed in 2025, as current. It is printed in the TCNA compilation of ANSI A108, A118 and A136.1, July 2026 edition.
Two further sections complete the set. Thermal shock resistance must exceed 3.45 MPa (500 psi) (section 5.8), and the setting sections 5.1 and 5.2 require an initial set later than 2 hours, service within 7 days and water cleanability at 80 minutes. For comparison, ANSI A118.7-2019 asks a high performance cement grout for more than 20.7 MPa (3,000 psi) compressive strength, less than 0.20 % shrinkage at 28 days and water absorption below 5 %.
EN 13888-1:2022 and ISO 13007-3 reaction resin grout RG#
EN 13888-1:2022, published 2022-09-13 with its test methods in EN 13888-2:2022, replaced EN 13888:2009 and sorts tile grouts into CG1, CG2 (A, W), F and the reaction resin class RG. ISO 13007-3:2010, last reviewed and confirmed in 2025, carries the same RG class for international use. A product's declared RG values appear on its data sheet or, where one is issued, its declaration of performance, together with the EN 13888-2:2022 test behind each value. Cement and resin classes side by side are set out under EN 13888-1 and EN 13888-2 tile grout classes.
Is an ANSI A118.3 epoxy the same as an RG grout?#
Not necessarily: ANSI A118.3 and EN 13888 class RG test different properties by different methods, so a grout can carry one claim without the other. A118.3 tests quarry shear bond, tensile strength and thermal shock in its own sections, while RG values come from the EN 13888-2:2022 test methods, such as abrasion and flexural strength. A product sold in both markets shows each claim separately on its data sheet, and one claim does not establish the other.
How do you check an epoxy grout claim on a data sheet?#
Five checks confirm an epoxy grout claim on a data sheet, listed below in the order a specifier reads the sheet.
- Confirm the standard and its edition: ANSI A118.3-2021 (R2025) or EN 13888-1:2022 class RG, not an undated reference to "ANSI".
- Match each A118.3 section to its value: 5.5, 5.6, 5.7, 5.8, 5.3 and the setting sections 5.1 and 5.2.
- Separate the requirement column from the test result, and read each compressive result against the 24.1 MPa (3,500 psi) minimum.
- Check the test age and temperature printed beside each value, since strengths and times change with both.
- Attach the safety data sheet and the VOC statement, including the method behind the VOC figure.
The data-sheet edition matters as well: the Kerapoxy CQ data sheet used on this page is dated 2026-05-04, while SpectraLock PRO Premium DS-681 carries the revision code 1026 without a date.
How Do You Choose an Epoxy Grout?#
Epoxy grout is a good idea where stains, food acids or cleaning chemicals reach the joints and the installer can work within its working time. Where joints only need color at low cost, a cement grout to ANSI A118.7-2019 or class CG2 does the job at less material cost. The table below matches five situations to a grout class and its standard.
| Situation | Grout | Standard | Note |
|---|---|---|---|
| Stain-prone floors, commercial kitchens, food areas | Epoxy | ANSI A118.3-2021 (R2025); RG | No sealer needed |
| Chemical exposure | Epoxy, or furan for harsh chemicals | ANSI A118.3; ANSI A118.5-1999 (R2025) | Furan section below |
| Exterior or wet area on a budget | cement tile grout | ANSI A118.7-2019 or CG2 or better | TCNA guidance as cited on a Daltile exterior detail |
| No mixing, no sealer | premixed tile grouts | ANSI A118.19-2023 | Indentation test, no compressive test |
| Soft polished stone, glass, white porous stone | Epoxy after a test tile | ANSI A118.3; RG | Quartz filler can scratch, resin can stain |
Budget is the second axis of the choice. The Construction Specifier (2025-06-05) ranks grout material cost from ANSI A118.6 standard cement grout as the lowest, through A118.7 high performance cement grout and A118.19 premixed grout, to A118.3 epoxy grout as the highest. The higher price buys a higher strength minimum, 24.1 MPa (3,500 psi) against 20.7 MPa (3,000 psi), and joints that need no sealer. That strength, stain and cost trade-off between resin and cement is set out under epoxy grout vs cementitious grout.
When is epoxy grout the wrong product?#
Five situations call for another product or a test first, and they are listed below.
- Harsh chemicals or steam cleaning: furan grout to ANSI A118.5-1999 (R2025) is the joint material, not epoxy.
- Outdoor sun: UV exposure shifts the color of epoxy grout outdoors.
- Soft polished marble, glass and white porous stone: the filler can scratch and the resin can stain, so a spare tile is grouted and cleaned first.
- The waterproofing layer: no grout replaces the membrane under the tile.
- Machinery bases: equipment grouting takes epoxy machinery grouts, a flowable product tested under ASTM C579-23.
The downsides of epoxy grout follow from the same list plus two practical ones: a working time that shrinks as the temperature rises, and the highest material cost of the ANSI grout classes.
How Is Epoxy Grout Applied? Joints, Temperature, Coverage and Cure#
An epoxy grout job is decided before mixing: joints must be clean and deep enough, the tile tested for scratching and staining, and the substrate held inside the product's temperature window until the grout has cured. The work calls for an experienced installer, because the grout sets fast and its cleanup follows a technique of its own. In the US, the Ceramic Tile Education Foundation (CTEF) runs the CTI and ACT programs for tile installers.
Joint preparation and tile compatibility tests#
Joints are grouted only after the setting mortar has cured, and they must be clean and open to at least two-thirds of the tile depth (ANSI A108.10 guidance as cited on the Kerapoxy CQ data sheet). ANSI A108.10-2026 is the current edition of the grout installation standard. The table below lists the four preparation checks with their source.
| Check | Requirement | Source (data sheet, edition) |
|---|---|---|
| Setting mortar | Cured before grouting | Kerapoxy CQ (TDS 2026-05-04), citing ANSI A108.10 |
| Joint depth | Clean, open to at least 2/3 of the tile depth | Kerapoxy CQ (TDS 2026-05-04), citing ANSI A108.10 |
| Tile test | Soft polished marble, glass and white porous stone (Carrara, Thassos) tested on a spare tile | Kerapoxy CQ (TDS 2026-05-04) |
| Mix | No water added | Kerapoxy CQ (TDS 2026-05-04) |
The tile test answers two risks at once. The quartz filler can scratch soft polished marble and glass during cleaning, and white porous stone such as Carrara or Thassos marble can take up resin as a stain. Water plays no part in the cure, which is a resin-hardener reaction, so the mix is used as supplied and the joint is cleaned with water only within the working time.
Epoxy grout coverage per joint size#
Epoxy grout coverage falls as tiles get smaller, because a smaller tile puts more joint length into every square meter, even when the joint itself is narrower. The table below gives theoretical coverage from one data sheet for two tile formats, with the waste allowances printed on a second.
| Product (data sheet, edition) | Tile and joint | Theoretical coverage | Basis |
|---|---|---|---|
| Kerapoxy CQ (TDS 2026-05-04) | 152 x 152 x 6.4 mm (6 x 6 x 1/4 in) tile, 3.2 mm (1/8 in) joint | 14.8 m² per 3.79 L (159 ft² per US gal); 3.9 m²/L (calculated) | Theoretical, per US gal |
| Kerapoxy CQ (TDS 2026-05-04) | 25 x 25 x 6.4 mm (1 x 1 x 1/4 in) mosaic, 1.6 mm (1/16 in) joint | 5.2 m² per 3.79 L (56 ft² per US gal); 1.37 m²/L (calculated) | Theoretical, per US gal |
| SpectraLock PRO Premium (DS-681) | Any tile | Add 10 % waste; add 10 to 15 % more on unglazed quarry tile | Practical allowance |
A worked example shows the scale of a job. Inputs: 20 m² (215 ft²) of 152 x 152 x 6.4 mm (6 x 6 x 1/4 in) tile with 3.2 mm (1/8 in) joints; theoretical coverage 3.9 m²/L from the first table row; waste allowance 10 %. Result: 20 / 3.9 = 5.1 L, plus 10 % = 5.6 L (1.5 US gal) of mixed grout. Other tile and joint sizes are read from the product's own coverage table, and the joint-volume method behind such tables is explained with the tile grout and adhesive calculator.
Epoxy grout temperature window and cure times#
One product's data sheet (Kerapoxy CQ) requires the substrate at 16 to 32 °C (60 to 90 °F) for 72 hours and forbids propane heaters, which yellow the grout. Temperature sets every time on an epoxy grout job, because the resin-hardener reaction speeds up in heat and slows in cold. The table below lists the times printed on two data sheets, row by row with their temperature.
| Temperature | Product (data sheet, edition) | Working time or pot life | Tack-free | Light / heavy traffic | Stain resistance | Full cure |
|---|---|---|---|---|---|---|
| 4 °C (40 °F) | SpectraLock PRO Premium (DS-681) | 120 min | 12 h | 24 h / 48 h | 14 days | 28 days |
| 21 °C (70 °F) | SpectraLock PRO Premium (DS-681) | 80 min | 4 h | 12 h / 24 h | 7 days | 14 days |
| 35 °C (95 °F) | SpectraLock PRO Premium (DS-681) | 30 min | 2 h | 6 h / 12 h | 3 days | 7 days |
| 23 °C (73 °F), 50 % RH | Kerapoxy CQ (TDS 2026-05-04) | Pot life 45 to 60 min | Not stated | Foot traffic after 48 h | 10 to 14 days before immersion or chemicals | 14 days |
Data-sheet values of two named products; times change with temperature. The terms behind the columns are defined under pot life, working time and cure time.
Read across the rows of the first product in the table, working time falls from 120 minutes at 4 °C (40 °F) to 30 minutes at 35 °C (95 °F), and full cure falls from 28 days to 7 days. Heat therefore shortens the window for cleaning residue off the tile, and cold lengthens the wait before chemicals, cleaners or immersion reach the joint.
How Is Epoxy Grout Inspected, and Why Does It Fail?#
Epoxy grout failures trace to timing, temperature and tile choice: residue left past the working time hardens into haze, heaters and sun shift the color, and acids reaching the joint before a 7-day cure stain it. Tile choice adds two more failures, scratched soft stone or glass and resin stains on white porous stone. The table below lists seven failures with their cause and the check that catches each one.
| Failure | Cause | Check |
|---|---|---|
| Haze on the tile face | Residue cleaned after the working time | Cleaning finished within the working time at the site temperature |
| Yellowing | Propane heaters | Heat source on the job record |
| Color shift | UV exposure outdoors | Exposure of the area |
| Acid staining | Acids or cleaners before the 7-day cure | Grouting date against the first cleaning date |
| Scratched stone or glass | Quartz filler dragged during cleaning | Test tile before grouting |
| Resin stain on white porous stone | Resin taken up by the stone | Test tile before grouting |
| Joint attack | Harsh chemicals or steam cleaning | Exposure check; furan grout to ANSI A118.5 where it applies |
Inspection follows the cure. Kerapoxy CQ's data sheet (TDS 2026-05-04) sets a hardness check of the joints after 3 days, and the grouting date recorded on the job decides when cleaning, chemicals or immersion may start.
What Health, Safety and VOC Rules Apply to Epoxy Grout?#
Epoxy grout's hazards sit in the uncured liquids: the resin side and the amine hardener side both carry skin sensitization, the hardener can be corrosive, and the quartz filler adds dust when the powder is handled. The table below lists the classifications and limits with their instrument and date.
| Topic | Rule or classification | Instrument and date |
|---|---|---|
| Liquid epoxy resin (CAS 25068-38-6, EC 500-033-5) | Harmonised CLP Annex VI (index 603-074-00-8): H315, H317, H319, H411 | CLP Annex VI; ECHA, checked 2026-10-22 |
| BADGE (CAS 1675-54-3, EC 216-823-5) | Harmonised CLP Annex VI (index 603-073-00-2): H315, H317, H319 | CLP Annex VI; ECHA, checked 2026-10-22 |
| IPDA hardener (CAS 2855-13-2) | Harmonised CLP Annex VI: H302, H314, H317, H318 (index 612-067-00-9; Skin Sens. 1A at 0.001 % or more) | Regulation (EU) 2021/849 (ATP17), applicable since 2022-12-17 |
| TETA hardener | Harmonised CLP Annex VI (index 612-059-00-5): H312, H314, H317, H412 | CLP Annex VI |
| REACH Annex XVII | No epoxy-specific restriction; entry 74 (diisocyanates) does not apply to epoxy-amine systems | Regulation (EC) No 1907/2006 |
| California Proposition 65 | Epoxy resin and BADGE not listed as such | OEHHA list dated 2026-07-31 |
| Quartz (crystalline silica) (CAS 14808-60-7) | No Annex VI entry; no hazard statement in a majority of ECHA C&L notifications; classification is product-specific, see supplier SDS | ECHA, checked 2026-10-20 |
| Respirable crystalline silica, US construction | PEL 50 µg/m³ 8-h TWA; action level 25 µg/m³ | OSHA 29 CFR 1926.1153, effective 2016-06-23 |
| Respirable crystalline silica, EU | Binding limit 0.1 mg/m³, 8-h TWA | Directive (EU) 2017/2398 |
| VOC, South Coast | Grout category 65 g/L (0.54 lb/gal), less water and exempt compounds | SCAQMD Rule 1168, amended 2022-11-04 |
Epoxy resin and amine hardener hazards#
The hazard line of liquid epoxy resin (CAS 25068-38-6, EC 500-033-5) reads: Harmonised CLP Annex VI (index 603-074-00-8): H315, H317, H319, H411. For BADGE (bisphenol A diglycidyl ether, CAS 1675-54-3) it reads: Harmonised CLP Annex VI (index 603-073-00-2): H315, H317, H319. Where the hardener contains IPDA (CAS 2855-13-2), the line is Harmonised CLP Annex VI: H302, H314, H317, H318, under index 612-067-00-9 as set by Regulation (EU) 2021/849 and applicable since 2022-12-17, with skin sensitization category 1A from 0.001 %. Where it contains TETA, index 612-059-00-5 lists H312, H314, H317 and H412. For one formulated product, SpectraLock PRO Premium's data sheet (DS-681) warns that the liquid components cause severe skin burns and serious eye damage, and every other product is read from its own SDS.
Protection follows from skin sensitization, the main occupational hazard of epoxy systems: nitrile or butyl gloves, sleeves and eye protection, and no skin contact with uncured resin. REACH Annex XVII holds no epoxy-specific restriction, and entry 74 on diisocyanates does not apply to epoxy-amine systems. Under California Proposition 65, epoxy resin and BADGE are not listed as such on the OEHHA list dated 2026-07-31, while their precursors bisphenol A and epichlorohydrin are listed. Mixture chemistry and the full hazard picture of the binder are covered under epoxy resins and hardeners.
Quartz filler and respirable crystalline silica#
The hazard line of quartz (crystalline silica), CAS 14808-60-7, reads: No Annex VI entry; no hazard statement in a majority of ECHA C&L notifications; classification is product-specific, see supplier SDS. Dust arises when the filler powder of a three-part kit is poured and mixed. In US construction, OSHA 29 CFR 1926.1153 sets a permissible exposure limit of 50 µg/m³ as an 8-hour time-weighted average and an action level of 25 µg/m³, effective 2016-06-23, and its housekeeping section (f) rules out dry sweeping, dry brushing and compressed air for cleanup. In the EU, Directive (EU) 2017/2398 sets a binding limit of 0.1 mg/m³ of respirable crystalline silica over 8 hours.
VOC limits and emission labels for epoxy grout#
SCAQMD Rule 1168, amended 2022-11-04, limits the Grout category to 65 g/L (0.54 lb/gal), less water and exempt compounds, and defines Grout as "a cement-based sealant formulated to fill or seal gaps, including those associated with tile installations". The definition is written around cement-based products, so the VOC statement of an epoxy grout names the method and basis behind its own figure.
Kerapoxy CQ reports 8 g/L (0.07 lb/gal) by the Rule 1168 method (TDS 2026-05-04), and SpectraLock PRO Premium reports 0.031 g/L (0.00026 lb/gal) total VOC (DS-681). UL GREENGUARD certification under UL 2818 is an emissions certification, not a VOC content limit. Rule 1168 subdivision (j)(7) exempts polymer-free dry mixes that are only mixed with water from the labeling subdivision (g) only, which leaves resin grouts outside it. Other rules and categories are compared under VOC limits for construction chemicals.
How Much Does Epoxy Grout Cost?#
Grouting tile costs USD 32.72 to 60.06 per m² (USD 3.04 to 5.58 per ft²) installed (labor plus job supplies, basic, all grout types), US national average, in the homewyse cost guide dated May 2026. That range does not separate epoxy from cement grouts, and epoxy sits at the top of the ANSI grout cost ranking that The Construction Specifier published on 2025-06-05. One material reference point exists for a single product: a SpectraLock PRO Premium full three-part kit (Parts A, B and C) was listed at USD 135.19 (material) by one US online retailer in a search snippet dated 2026-10. A job budget for epoxy grouting therefore comes from quotes on the area, the tile format, the joint width and the A118.3 or RG claim. The table below lists the three cost references with their dates.
| Item | Range | Region | Date | Source type |
|---|---|---|---|---|
| Installed grouting (labor plus job supplies, basic, all grout types) | USD 32.72 to 60.06 per m² (USD 3.04 to 5.58 per ft²) | US national average | 2026-05 | Cost guide (homewyse) |
| SpectraLock PRO Premium full three-part kit (material) | USD 135.19 per full kit | US, one online retailer | 2026-10 | Retailer listing (search snippet) |
| Relative material cost ranking | ANSI A118.6 lowest, then A118.7, A118.19, A118.3 highest | US | 2025-06-05 | Trade magazine (The Construction Specifier) |
The material price is one product at one retailer; the installed range covers all grout types together.
What Are the Alternatives to Epoxy Tile Grout?#
Five product classes compete with epoxy tile grout, and each wins where cost, mixing, chemical load or temperature rules epoxy out. Cement grouts win on cost, premixed grouts on handling, furan grout on harsh chemicals and heat, modified epoxy emulsion grout where ANSI A118.8 is specified, and a resin lining where the whole floor carries the chemical load. The table below lists the alternatives with their chemistry and standard.
| Alternative | Chemistry | When it wins | Standard |
|---|---|---|---|
| cement tile grout | Portland cement and sand, polymer in high performance grades | Cost; exterior and wet areas with sealing | ANSI A118.6-2019, A118.7-2019; EN CG1, CG2 |
| premixed tile grouts | Acrylic, urethane or hybrid dispersion, no cement | No mixing, no sealer | ANSI A118.19-2023 |
| Furan grout (section below) | Furan mortar and grout | Harsh chemicals, high temperature, steam cleaning | ANSI A118.5-1999 (R2025) |
| Modified epoxy emulsion grout | Epoxy emulsion modified mortar and grout | Specifications that name A118.8 | ANSI A118.8-1999 (R2025) |
| chemical-resistant linings | Resin lining over the whole floor | The floor, not only the joints, takes the chemical load | Per lining system |
| epoxy grout vs cementitious grout | Side-by-side comparison | Strength, stain and cost trade-off | ANSI A118.3 vs A118.7 |
Premixed grout replaces the compressive test with an indentation test: ANSI A118.19-2023 limits indentation to 1.14 mm (0.045 in) under at least 6.9 MPa (1,000 psi) after 28 days dry, and sets no compressive strength requirement.
Furan and modified epoxy emulsion grouts (ANSI A118.5, A118.8)#
Furan mortars and grouts, specified by ANSI A118.5-1999 and reaffirmed in 2025, are the tile joint material for harsh chemicals and high temperatures where epoxy grout is not suited, including steam cleaning. The Kerapoxy CQ data sheet draws the same line, directing harsh chemicals and steam cleaning away from its epoxy grout to ANSI A118.5 furan.
ANSI A118.8-1999, also reaffirmed in 2025, covers modified epoxy emulsion mortars and grouts, a third resin-based route listed as current on the TCNA standards status page of 2026-09-10. The requirement values of furan and A118.8 products sit in each standard's own text and on the product data sheet, not in the A118.3 sections above.
Epoxy Grout Grades, Packaging and Sourcing#
Epoxy grouts are sold as three-part kits (resin, hardener, filler powder) or pre-filled two-component packs, and buyers compare them on the A118.3 or RG claim, filler color range, working time and VOC basis.
A data-sheet comparison across makers is the core of sourcing, and the method for that comparison is set out under construction chemicals manufacturers and suppliers. The five items a buyer checks before ordering are listed below.
- Standard and edition: ANSI A118.3-2021 (R2025), EN 13888-1:2022 class RG or ISO 13007-3:2010 RG, named on the data sheet.
- Section values: each A118.3 section with its result, compressive above 24.1 MPa (3,500 psi) and shrinkage below 0.25 %.
- Working time at 21 °C (70 °F): and at the expected site temperature, since every time on the sheet changes with temperature.
- Safety data sheet: the hardener amines and their hazard lines, such as IPDA or TETA.
- VOC statement: the figure in g/L (lb/gal) with the method behind it.
Where Does Epoxy Grout Fit in a Tile Installation System?#
Epoxy grout is the last layer of a tile system: the membrane keeps water out of the substrate, the adhesive bonds the tile, and the grout seals the joint surface against stains, so it replaces neither layer below. The adhesive bed needs at least 95 % mortar contact in wet areas and exteriors (ANSI A108.5-2023 practice).
Pools add a fixed sequence: the bare shell passes a tightness test to ACI SPEC-350.1-22, a membrane to EN 14891:2017 class P or ANSI A118.10-2023 follows, and the epoxy grout comes last. The table below lists the layers of the system with their product class and standard.
| Layer | Product class | Standard |
|---|---|---|
| Membrane | tile waterproofing membranes | ANSI A118.10-2023; EN 14891:2017 (EN 14891:2012 stays the CE-marking basis) |
| Crack isolation | uncoupling and crack-isolation membranes | ANSI A118.12-2014 (R2024) |
| Adhesive | tile adhesive classes | A118.3 setting epoxy or EN C2 cement adhesive |
| Large or heavy tile | large and heavy tile mortars | ANSI suffix H (A118.4H, A118.15H) |
| Joint | Epoxy tile grout | ANSI A118.3-2021 (R2025); RG |
Epoxy tile grout FAQs#
The five questions below cover the queries that sit next to epoxy grout: concrete patching, old grout, machinery grout, waterproofing and regular grout.
Can you use tile grout to patch concrete?#
No: tile grouts fill tile joints, and spalled or broken concrete is rebuilt with repair mortars classed R1 to R4 by EN 1504-3:2005.
Repair mortar classes and their selection are covered under concrete repair mortars.
Can epoxy grout go over old grout?#
No: epoxy grout needs clean joints open to at least two-thirds of the tile depth, so old grout is removed first. That depth rule is ANSI A108.10 guidance as cited on product data sheets, and A108.10-2026 is the current edition.
Is epoxy grout the same as epoxy machinery grout?#
No: epoxy machinery grout is a flowable, high-strength product for equipment bases tested under ASTM C579-23, while epoxy tile grout fills tile joints under ANSI A118.3.
Is epoxy grout waterproof?#
No: epoxy grout is non-porous and resists water and stains, but it is not a waterproofing layer, and wet areas need a membrane under the tile.
Membrane types for showers and wet areas are covered under tile waterproofing membranes.
Is epoxy grout better than regular grout?#
It depends on exposure: epoxy exceeds cement grout's A118.7 compressive minimum and needs no sealer, but costs more and is harder to install. ANSI A118.3 requires more than 24.1 MPa (3,500 psi) against 20.7 MPa (3,000 psi) for A118.7, and epoxy ranks highest in material cost among the ANSI grout classes (The Construction Specifier, 2025-06-05).