I am unclear about the coverage rates for GacoRoof. The package and the brochure seem to have different rates. Why is this?
The confusion between the brochure and package is this: because TWO coats are required, the coverage for the COMPLETED project is 1 gallon per 50 square feet. (You can use this rate to figure out how many gallons you need to purchase). The APPLICATION rate (the amount used to gauge the proper thickness when rolling the silicone coating onto your roof ), is 1 gallon per 100 square feet.
So, how much Acrylic roof coating do I need for the same job?
Acrylics typically require more than DOUBLE the amount of GacoRoof coating for the same roof project. For most acrylics, you need to apply one coat of sealant and/or primer, PLUS a base coat, PLUS one or two additional top coats at a rate of 1 gallon per 100 square feet. You'll need 1 gallon of primer and 2-4 gallons of acrylic roof coating for every 100 feet. When you include accessory products, such as patch compound, fabric and sealer, the cost of an acrylic coating really adds up. And don't forget that the typical acrylic roof only lasts about 3-5 years before a recoat is required!
Are you sure my roof does not need a primer coat? Do I need to prime metal flashing or other metal surfaces?
Metal flashing should either be primed with an exterior metal primer, or lightly sanded. Most other roof surfaces do not require a primer before applying GacoRoof. See the list of acceptable substrates below.
OK, so how does GacoRoof compare to acrylic roof coatings?
  1. GacoRoof has a 50-year limited warranty. GacoRoof will last as long as the substrate it is applied to. Acrylics, if they have a warranty at all, warranty only 3-5 years. One acrylic offers an 8-year warranty BUT you have to recoat every 3 years.
  2. GacoRoof can withstand PERMANENT ponding water. There are no acrylics that will stand up to the stress of permanent ponding water without bubbling or adhesive failure.
  3. GacoRoof can be applied in a wide temperature range (32-120 degrees F). Acrylics cannot be applied at temperatures below 55 degrees or above 90 degrees.
  4. All acrylics require a primer coat. GacoRoof does not require any primer, sealer or patch compound.
  5. GacoRoof does not require a recoat. Silicone is inert, and does not degrade or wear away. Acrylics require a recoat every 3-5 years.
What substrates does GacoRoof adhere to?
GacoRoof adheres to a multitude of roof types. Suitable substrates include silicone, aged asphalt (not for use on 3-tab asphalt or architectural shingles), aged EPDM and TPO/CPA (may require GacoFlex E5320), built-up, cap sheet, composite, concrete, fiberglass, metal, modified bitumen, torchdown and sprayed polyurethane foam. GacoRoof is perfect for Residential and Commercial buildings, as well as flat and low-pitched roofs, mobile homes, RV's and campers.
What about EPDM & TPO Roofs?
GacoRoof may be applied to Aged EPDM and TPO roofs but may require the use of GacoFlex E5320 2-Part Epoxy Primer/Filler. To verify adhesion, use the GacoRoof AdhesionTestKit, which provides results in just 24 hours. If the test reflects poor adhesion, prime all surfaces with GacoFlex E5320 according to label directions. Call toll-free (866) 422-6489 for more information and specific recommendations.
Does GacoRoof come in other colors?
GacoRoof is available in White, Gray, Green, Light Tan, Rustic, Medium Blue, Black, Brown and Red. GacoRoof White may be tinted Gray using GacoRoof Colorant, which can then be applied as the base or top coat.
Can GacoRoof be applied with a sprayer?
GacoRoof should not be sprayed because it is too thick for spray equipment. If GacoRoof is thinned with mineral spirits, it no longer meets the regulations for minimum V.O.C.'s (volatile organic compounds).
What is skinning? What happens if I don't use the entire pail right away and a skin forms?
Skinning is when the topmost layer of coating begins to cure in the pail. Silicone is moisture-cured, so high heat and humidity will cause the product to skin. If surface skins, remove skinned material from container. To minimize skinning over several days, pour a thin layer of 100% mineral spirits on top of product until it is completely covered and do not move pail until ready to reuse. When ready, stir thoroughly with a power mixer. Keep container tightly closed between applications to minimize surface skinning.
Does GacoRoof have a UL (Underwriters Laboratory) Approval Rating?
Yes, GacoRoof is UL rated when applied to a non-combustible surface.
Is there a mildicide in GacoRoof? Does GacoRoof mold or mildew?
There is no mildicide in GacoRoof, because mildew does not grow on the surface of GacoRoof. Unlike acrylic coatings, GacoRoof is inert and does not provide a food source for mildew or mold.
Can my GacoRoof be pressure washed?
You can pressure wash GacoRoof at a low pressure (below 2,500 psi).
I know that GacoRoof is perfect for flat roofs. Can I use GacoRoof on my peaked roof?
GacoRoof does cover peaked roofs as well as flat roofs. Use extreme caution when on a pitched roof. Follow all safety guidelines to avoid injury. The reason that we emphasize our flat roof coverage is that flat roofs are notorious for having puddles and drainage problems and acrylics degrade rapidly under those conditions. Up until now, the only choice for building owners with flat roofs was smelly hot asphalt or recoating every 3 years with an acrylic.
Since both coats are white, how can I see where to apply the second coat?
Snap chalk lines as needed to see where to apply the second coat. Alternatively, GacoRoof Colorant can be used to tint one coat (base or top) gray, providing greater color contrast between the two coats.
Can GacoRoof be applied to roof decks or walkways?
Silicone can be slick, especially when the surface is wet, so GacoRoof should not be used for areas with foot traffic. GacoDeck Kit is a better choice for roof decks.
How many square feet does the top coat cover?
133 square feet per coat
How do you apply the system?
Complete instructions are inside the GacoDeck brochure, the GacoDeck Kit pail and may be found on our website by clicking this link: GacoDeck Kit Application Instructions  
What kind of caulk is the best kind to use?
GacoDeckFill is specially formulated and the only approved joint filler for the GacoDeck system. It is a water-borne, elastomeric acrylic filler that utilizes 20% post-consumer recycled content to ensure an environmentally-friendly and durable, yet flexible joint filler.
Is everything really in that 5-gallon bucket? Tape, granules, caulk, roller, DVD, paintbrush? How can it be in there without floating in the coating?
Trust us, it's all in there, and it's not floating in coating. The GacoDeck Kit package was specially designed to allow all of the components to fit (and remain secure and dry) in one container.
How do I clean up after application? Does the coating come out of clothing?
Use normal precautions to avoid getting the coating on your skin (wear long pants, socks, long sleeves, and work gloves). If you do get GacoDeck coating on your skin, you can scrub it off with soap and water. GacoDeck coating will not come out of clothing or shoes.
What do I do with the bucket after I am finished?
You can leave the bucket uncovered overnight to allow the residual coating to dry. Pull the dry coating out of the bucket and dispose of it in your trash container. The dried coating is inert. The bucket can then be reused or recycled.
What kind of primer should I use for flashing?
You can use any standard metal primer available at your hardware store.
How can I know if I am applying the recommended coverage? How far does one roller full of coating cover?
We estimate that each roller-full should cover 4 sq. ft on the base coat. The first coat tends to soak into the wood more and does not cover as much area as the following coats. The next coats should cover 6-8 square feet per roller-full.
How do I know if my deck can be re-coated with the GacoDeck Kit system?
If the existing deck coating or membrane remains fully adhered to the substrate, it can be recoated.
What substrates should not be coated with the GacoDeck Kit system?
GacoDeck Kit will not go over torchdown, BUR, OSB and CDX plywood, or on decks with no slope or standing water (¼-inch puddle for 1 week).
Can I recoat over Hypalon® or urethane? What preparations should I make for an existing deck?
To prepare any deck for a new topcoat, it must be cleaned by pressure washing or thorough scrubbing with GacoWash Concentrated Cleaner. Rinse well and allow to dry 24 hours. If your existing deck coating is waterproof and in good condition, you may recoat the surface using one coat of GacoDeck Primer, followed by one or two coats of GacoDeck TopCoat for Maintenance. If the deck coating leaks, is worn, or has cracks or holes, you may recoat the surface. For decks with "alligator" cracks in the coated surface, or cracking at plywood seams, we recommend taking off the old tape with a sander using 80-grit sandpaper. After re-taping the seams, and caulking, apply a coat of GacoDeck Primer, followed by a full application of the GacoDeck Kit system.
Why can't I use GacoDeck Kit over a torchdown roof?
The GacoDeck Kit coating is a much harder acrylic compared to other acrylic roofing products on the market. Most acrylic roof coatings are soft acrylics, which does not make for a good walking surface. For torchdown roofs that are not intended as walking surfaces, GacoRoof provides a bright white waterproof surface.
Will the tape show through the coating? How can I hide visible lines from the tape used on seams?
A seamless finish is easy to achieve. Lightly sand the edges of the tape with a medium grit sandpaper before the first base coat is applied. If you do not sand the edges of the tape, the seams may be visible after the deck is finished.
Can I apply the GacoDeck Kit over a clear sealed plywood such as Thompson Water-Seal or Wood-Life?
Wood sealers often contain paraffin, which prevents paint or coatings from adhering to the wood. If you have sealed your deck surface, you must use Strip XL, manufactured by Bio Wash, to strip off the sealer. Test the surface after stripping the sealer by spraying with water and seeing if the water still beads. If the water does not bead, the sealer has been stripped. After testing, allow the surface to dry for 24 hours.
How do I determine slope?
Gaco recommends ¼-inch slope. Check your slope with a level.
Is tape better than metal flashing at edges and termination points?
Both are equally preferable. Some types of siding will not allow metal flashing to fit up under the siding. For decks that abut this siding, tape must be used. On outside edges of your deck, we recommend metal flashing. Metal flashing creates a metal drip edge, to prevent water from running underneath the deck, and to prevent soiling the fascia board.
How long before furniture can be placed on the deck after the deck has been coated?
48 hours. We recommend that deck furniture have rubber tipped legs to avoid scraping the deck surface.
Should I caulk gaps in plywood? Should I caulk over nails or screws?
Butt the plywood sheets against one another. Fill in any gaps, including nail indentations, with GacoDeckFill before taping or coating.
Can I put planters on my deck?
Yes, you may put planters on your deck. To avoid discoloring or damaging the GacoDeck Kit coated surface, planters must be up off the surface. Plant stands, rollers, or glass blocks can be used to lift planters and pots up off of the deck surface. Avoid puddles of water under planters or hanging baskets.
Can I have a hot tub on my deck?
There are two ways to purify and maintain the water in a hot tub. One is a chlorine-based system, and the other is a bromide-based system. Chlorine-based systems can cause damage and discoloration to the coating surface from hot, chlorinated water splashing on to the deck surface. Bromide-based systems (such as Baqua Spa) can be used with the GacoDeck Kit coating. It is always a good idea to minimize splashes of chemically-treated water on your deck surface. If splashes do occur, rinse the area with clean water.
How many square feet does the primer cover? How long does it take to dry?
The GacoDeck Primer covers 200 square feet. The primer should be dry to the touch before applying the system.
My deck surface is still "sticky" and has not cured. What should I do?:
If the temperature drops more than 20 °F overnight after you coat your deck, your deck may not cure (harden) completely. Do not place heavy objects or furniture on your deck until it has cured. The following process removes small amounts of surfactents that can rise to the surface of a newly coated deck and inhibit curing time. If your deck coating is still sticky or tacky after 48 hours, wet the deck surface, apply GacoWash Concentrated Cleaner and agitate with a broom. Rinse the deck thoroughly and allow to dry. Within 48 hours, the deck surface should be cured.
Can I use the GacoDeck Kit system to add a skid-resistant surface around a pool?
Yes, the GacoDeck Kit system can be used around pool surrounds. It is always a good idea to minimize splashes of chemically-treated water on your deck surface, because repeated exposure to heavy doses of chlorine may enhance fading and embrittle the coating.
Can I use my barbeque on my deck?
Yes, you can barbeque on your deck. Take care to avoid any hot ashes or coals on the deck surface. If oil or soot collects on the deck surface, it may discolor. Wipe up any spills immediately.
I coated my deck in the afternoon, and early the next morning, I noticed that the surface appeared splotchy and stained. What happened? What can I do about it?
Although this condition looks unattractive, it will not have any effect on the life of the coating. It's known as surfactant leaching, or surfactant bleed. Surfactants are water-soluble additives that insure the stability of the latex coatings, and they are sensitive to moisture during the drying period. If the drying process is interrupted by moisture, such as dew, fog, rain or humidity, surface staining may occur. To treat surfactant bleed, wash the surface with household detergent and water and rinse well (the longer the stain remains on the surface, the more difficult it can be to remove). Allow the surface to dry and continue with your application. Surfactant bleed is not uncommon during the first 30 days after an application.
The GacoDeckKit instructions say that the coating should be applied when no rain is imminent. I live in a rainy climate where rain is always imminent. Can I still apply the GacoDeck Kit?
Of course you can apply the GacoDeck Kit system. You may want to secure a large tarp over the area to be coated to protect the surface from rain and moisture.
I've been using textured black tape strips to make my stairs skid resistant, but the tape is always curling and coming up from the surface. Can I use the GacoDeck Kit to provide a skid-resistant surface on pressure-treated wood stair treads?
Yes you can! No primer, tape or caulking is required. For a small stairway, one jar of GacoGrip Texture Granules and 1 gallon of GacoDeck TopCoat may be adequate. Remove any textured tape or adhesive that remains on the surface. Two coats of GacoDeck TopCoat should be applied. Then mix in the granules with the remaining coating, and apply two more coats to the stairway.