{"product_id":"f-ball-stopgap-f77-epoxy-damp-proof-membrane","title":"F. Ball Stopgap F77 Epoxy Damp Proof Membrane","description":"\u003cdiv class=\"wwfs-product-description\"\u003e\n\n\u003cdiv class=\"wwfs-product-intro\"\u003e\n\u003cp\u003e\u003cstrong\u003eF. Ball Stopgap F77\u003c\/strong\u003e is a professional, solvent-free, two-part epoxy resin system that cures to form a high-performance waterproof surface membrane. It impedes residual construction moisture and rising damp in suitable concrete and sand\/cement screeds before smoothing compounds, adhesives and floor coverings are installed.\u003c\/p\u003e\n\n\u003cp\u003eApplied as a single coat, F77 can be used at subfloor relative humidity readings of up to 98% RH. It cures from approximately three hours at 20°C, making it ideal for fast-track domestic and commercial flooring installations where waiting for the subfloor to dry naturally would cause unnecessary delays.\u003c\/p\u003e\n\n\u003cp\u003eStopgap F77 is supplied as a pre-measured resin and hardener kit and is available from WWFS in practical 7kg and 14kg sizes.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eKey Benefits\u003c\/h2\u003e\n\n\u003cdiv class=\"wwfs-benefit-list\"\u003e\n\u003cul\u003e\n\u003cli\u003eProfessional two-part epoxy waterproof surface membrane.\u003c\/li\u003e\n\u003cli\u003eImpedes residual construction moisture and rising damp.\u003c\/li\u003e\n\u003cli\u003eSingle-coat application at readings up to 98% RH.\u003c\/li\u003e\n\u003cli\u003eSuitable over correctly commissioned cementitious underfloor heating screeds up to 90% RH.\u003c\/li\u003e\n\u003cli\u003eRapid curing from approximately three hours at 20°C.\u003c\/li\u003e\n\u003cli\u003eBlack pigmentation helps installers visually check coverage.\u003c\/li\u003e\n\u003cli\u003eSuitable beneath compatible Stopgap smoothing compounds and flooring adhesives.\u003c\/li\u003e\n\u003cli\u003eAllows earlier installation of suitable floor coverings.\u003c\/li\u003e\n\u003cli\u003eSolvent-free formulation.\u003c\/li\u003e\n\u003cli\u003eAvailable in 7kg and 14kg kits.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eIdeal For\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003ePrepared concrete subfloors.\u003c\/li\u003e\n\u003cli\u003ePrepared sand and cement screeds.\u003c\/li\u003e\n\u003cli\u003eNew-build concrete containing residual construction moisture.\u003c\/li\u003e\n\u003cli\u003eDomestic renovation projects.\u003c\/li\u003e\n\u003cli\u003eCommercial and fast-track flooring installations.\u003c\/li\u003e\n\u003cli\u003eCorrectly commissioned cementitious underfloor heating screeds.\u003c\/li\u003e\n\u003cli\u003eProjects receiving wood flooring, LVT, vinyl, carpet or another suitable floor covering.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cdiv class=\"wwfs-advice-box\"\u003e\n\u003ch3\u003eProfessional Advice\u003c\/h3\u003e\n\n\u003cp\u003eAlways test and record the subfloor moisture level before choosing the application rate. Stopgap F77 must be applied to a clean, absorbent and slightly textured surface. Remove laitance, surface hardeners, adhesive contamination, oil, grease and anything else that could prevent adhesion. Power-floated concrete must be mechanically prepared.\u003c\/p\u003e\n\n\u003cp\u003eThe substrate should have a surface strength greater than 1.5N\/mm². The cured membrane must form a continuous, glossy black coating without pinholes, weak areas or missed sections. Never exceed the specified coverage rate, as spreading the product too thinly may prevent it from providing the required moisture protection.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eCoverage and Application Guide\u003c\/h2\u003e\n\n\u003cdiv class=\"wwfs-coverage-guide\"\u003e\n\n\u003cdiv class=\"wwfs-coverage-item\"\u003e\n\u003ch3\u003eUp to 85% RH\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication rate:\u003c\/strong\u003e Approximately 2.5m² per kg.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTrowel:\u003c\/strong\u003e STYCCOBOND A2 trowel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e7kg coverage:\u003c\/strong\u003e Approximately 17.5m².\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e14kg coverage:\u003c\/strong\u003e Approximately 35m².\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"wwfs-coverage-item\"\u003e\n\u003ch3\u003eAbove 85% RH and Up to 98% RH\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication rate:\u003c\/strong\u003e Approximately 1.8m² per kg.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTrowel:\u003c\/strong\u003e 1.5mm × 5mm trowel supplied with the kit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e7kg coverage:\u003c\/strong\u003e Approximately 12.5m².\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e14kg coverage:\u003c\/strong\u003e Approximately 25m².\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"wwfs-coverage-item\"\u003e\n\u003ch3\u003eUnderfloor Heating Screeds Up to 90% RH\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication rate:\u003c\/strong\u003e Approximately 1.8m² per kg.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTrowel:\u003c\/strong\u003e 1.5mm × 5mm trowel supplied with the kit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e7kg coverage:\u003c\/strong\u003e Approximately 12.5m².\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e14kg coverage:\u003c\/strong\u003e Approximately 25m².\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003c\/div\u003e\n\n\u003cdiv class=\"wwfs-important-box\"\u003e\n\u003ch3\u003eOne Coat – Different Application Weights\u003c\/h3\u003e\n\n\u003cp\u003eStopgap F77 is a one-coat system at both application rates. Higher moisture readings require a heavier coat applied with the supplied 1.5mm × 5mm trowel, rather than two standard coats.\u003c\/p\u003e\n\n\u003cp\u003eImmediately back-roll the applied epoxy with a pre-coated paint roller to flatten the ridges and create an even, continuous and pinhole-free membrane. Where a very absorbent surface leaves a subdued shine, or pinholes or weak areas remain, a second application will be required.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\n\u003ctable class=\"wwfs-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eProduct Type\u003c\/th\u003e\n\u003ctd\u003eSolvent-free, two-part epoxy waterproof surface membrane\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003cth\u003eAvailable Sizes\u003c\/th\u003e\n\u003ctd\u003e7kg and 14kg kits\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003cth\u003eComponents\u003c\/th\u003e\n\u003ctd\u003ePre-measured resin and hardener\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003cth\u003eColour\u003c\/th\u003e\n\u003ctd\u003eBlack\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003cth\u003eMaximum Moisture Reading\u003c\/th\u003e\n\u003ctd\u003eUp to 98% RH on suitable cementitious subfloors\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003cth\u003eUnderfloor Heating\u003c\/th\u003e\n\u003ctd\u003eUp to 90% RH on correctly commissioned cementitious heated screeds at approximately 1.8m² per kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003cth\u003eWorking Time\u003c\/th\u003e\n\u003ctd\u003eApproximately 30 minutes at 20°C once mixed and poured onto the floor\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003cth\u003eCuring Time\u003c\/th\u003e\n\u003ctd\u003eFrom approximately three hours at 20°C\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003cth\u003eApplication\u003c\/th\u003e\n\u003ctd\u003eSpecified notched trowel followed immediately by back-rolling\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003cth\u003eSuitable Substrates\u003c\/th\u003e\n\u003ctd\u003ePrepared, clean and absorbent concrete and sand\/cement screeds\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003cth\u003eMinimum Substrate Strength\u003c\/th\u003e\n\u003ctd\u003eGreater than 1.5N\/mm²\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003cth\u003eIndoor Use\u003c\/th\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eHow to Apply Stopgap F77\u003c\/h2\u003e\n\n\u003ch3\u003e1. Test the Subfloor Moisture\u003c\/h3\u003e\n\n\u003cp\u003eUse an appropriate calibrated hygrometer to establish and record the relative humidity of the subfloor. The reading determines the required application rate and coverage.\u003c\/p\u003e\n\n\u003ch3\u003e2. Prepare the Surface\u003c\/h3\u003e\n\n\u003cp\u003eRemove laitance, surface treatments, weak material and contamination to produce a clean, absorbent and slightly textured surface. Power-floated concrete must be mechanically prepared. New concrete and sand\/cement screeds should normally be left for at least seven days before preparation and application.\u003c\/p\u003e\n\n\u003ch3\u003e3. Repair or Pre-Smooth Where Required\u003c\/h3\u003e\n\n\u003cp\u003eRough, uneven or damaged cementitious subfloors must be repaired or pre-smoothed before applying F77. Suitable products can include Stopgap 1200 Pro or another compatible Stopgap product selected for the substrate and required depth.\u003c\/p\u003e\n\n\u003cp\u003eAny smoothing compound installed beneath the membrane must be fully dry and sufficiently strong before F77 is applied. Take care to minimise pinholes in the pre-smoothed surface.\u003c\/p\u003e\n\n\u003ch3\u003e4. Mix the Complete Kit\u003c\/h3\u003e\n\n\u003cp\u003eAdd all of the hardener to the resin container. Mix using a suitable power whisk and low-speed drill for approximately two minutes, scrape the sides and base of the container, and then continue mixing for a further two to three minutes until a uniform colour and consistency are achieved.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eMix only in full packs. Do not split the kit.\u003c\/strong\u003e Incomplete or incorrectly proportioned mixing can leave soft, uncured areas and render the membrane ineffective.\u003c\/p\u003e\n\n\u003ch3\u003e5. Apply Immediately\u003c\/h3\u003e\n\n\u003cp\u003eOnce mixed, pour the product onto the prepared floor immediately. Leaving mixed epoxy inside the container significantly reduces its working time.\u003c\/p\u003e\n\n\u003cp\u003eFor readings above 85% RH and up to 98% RH, or commissioned underfloor heating screeds up to 90% RH, spread the membrane using the supplied 1.5mm × 5mm trowel at approximately 1.8m² per kg.\u003c\/p\u003e\n\n\u003cp\u003eFor readings up to 85% RH, use a STYCCOBOND A2 trowel at approximately 2.5m² per kg.\u003c\/p\u003e\n\n\u003ch3\u003e6. Back-Roll the Membrane\u003c\/h3\u003e\n\n\u003cp\u003eImmediately back-roll the applied F77 using a pre-coated paint roller. This flattens the trowel ridges and helps form an even, glossy, continuous and pinhole-free coating.\u003c\/p\u003e\n\n\u003ch3\u003e7. Allow the Membrane to Cure\u003c\/h3\u003e\n\n\u003cp\u003eAt approximately 20°C, F77 can cure in around three hours. Cooler temperatures will extend the curing time. Do not proceed until the entire surface is hard, fully cured and tack-free.\u003c\/p\u003e\n\n\u003ch2\u003eCompatible Follow-On Products\u003c\/h2\u003e\n\n\u003cp\u003eOnce F77 has fully cured, apply Stopgap P141 Primer neat before installing most Stopgap smoothing compounds.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eTypical system:\u003c\/strong\u003e\u003cbr\u003e\nPrepared cementitious subfloor → Stopgap F77 → neat Stopgap P141 → compatible Stopgap smoothing compound → flooring adhesive → floor covering.\u003c\/p\u003e\n\n\u003cp\u003eOn installations without underfloor heating, Stopgap 1200 Pro can be applied directly to fully cured F77 within 24 hours without P141. Where underfloor heating is present, prime the fully cured F77 with neat P141 before applying the selected compatible smoothing compound.\u003c\/p\u003e\n\n\u003cp\u003eF. Ball STYCCOBOND B95 wood flooring adhesive may be applied directly to fully cured Stopgap epoxy waterproof surface membranes within 24 hours under suitable conditions, provided the surface is smooth enough and the complete installation meets F. Ball’s requirements.\u003c\/p\u003e\n\n\u003cp\u003eDo not assume a Bona or another manufacturer’s adhesive can be bonded directly to F77. Unless the exact combination has been approved by the adhesive manufacturer, use F77 followed by P141 and a compatible Stopgap smoothing compound before applying the selected adhesive.\u003c\/p\u003e\n\n\u003cdiv class=\"wwfs-advice-box\"\u003e\n\u003ch3\u003eChoosing the Correct System\u003c\/h3\u003e\n\n\u003cp\u003eThe correct system depends on the substrate, moisture reading, floor covering, underfloor heating and whether the surface requires repair or levelling. Contact our flooring specialists before ordering if you are unsure which products are required.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"wwfs-important-box\"\u003e\n\u003ch3\u003eImportant Information\u003c\/h3\u003e\n\n\u003cul\u003e\n\u003cli\u003eApply Stopgap F77 only to a clean, absorbent and correctly prepared substrate.\u003c\/li\u003e\n\u003cli\u003eDo not apply it over calcium sulphate or anhydrite screeds.\u003c\/li\u003e\n\u003cli\u003eDo not use it where the subfloor is subject to hydrostatic pressure.\u003c\/li\u003e\n\u003cli\u003eDo not apply it directly over old bitumen adhesive residue. A suitable isolation and smoothing system may be required first.\u003c\/li\u003e\n\u003cli\u003eFor mastic asphalt or another non-standard substrate, obtain project-specific guidance from F. Ball Technical Services.\u003c\/li\u003e\n\u003cli\u003eDo not bridge structural or movement joints with F77.\u003c\/li\u003e\n\u003cli\u003eApply the membrane across the entire floor and terminate it correctly at the wall damp-proof course.\u003c\/li\u003e\n\u003cli\u003eThe floor temperature must be above 10°C and the substrate must be at least 3°C above the dew point during application.\u003c\/li\u003e\n\u003cli\u003ePrevent trafficking until the membrane is fully cured.\u003c\/li\u003e\n\u003cli\u003eUnderfloor heating must be correctly commissioned and switched off for 48 hours before, during and for 48 hours after installation of the membrane, smoothing compound and floor covering.\u003c\/li\u003e\n\u003cli\u003eRecommission underfloor heating gradually to prevent thermal shock.\u003c\/li\u003e\n\u003cli\u003eAlways follow the latest F. Ball Technical Data Sheet and relevant British Standards.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"wwfs-small-print\"\u003e\n\u003cp\u003eCoverage, working and curing times are approximate and depend on temperature, substrate texture, porosity, application technique and site conditions. Never exceed the specified coverage rate. Product specifications and manufacturer recommendations can change, so always consult the latest technical information before use.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003c\/div\u003e","brand":"F Ball","offers":[{"title":"7kg","offer_id":44662698999911,"sku":"rrx1789816853845","price":123.74,"currency_code":"USD","in_stock":true},{"title":"14kg","offer_id":44662699032679,"sku":"vhr1789816853846","price":225.29,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0669\/9109\/5911\/files\/f-ball-stopgap-f77-epoxy-damp-proof-membrane_1.webp?v=1789816882","url":"https:\/\/yearroundseamwear.shop\/products\/f-ball-stopgap-f77-epoxy-damp-proof-membrane","provider":"My Store","version":"1.0","type":"link"}