01 / Shop by project
What are you working on?
Pick the job. Each page has the right kit, the prep for your surface and a calculator for how much you need.
01
BasementsSeal porous concrete and block against seepage and damp, from the inside.See the kit
02
FoundationsCoat the outside before backfill. Bridges cracks up to 1/4".See the kit
03
Retaining wallsStop efflorescence and spalling on block, concrete or timber.See the kit
04
RoofsEPDM, shingle, metal, torch-down or concrete. No primer needed.See the kit
05
RV roofsEPDM, TPO, fiberglass and aluminum, without primer.See the kit
06
ShowersThe waterproof layer under tile. No pan liner to seam.See the kit
07
PoolsSeal gunite, plaster or fiberglass without replastering.See the kit
08
Fountains & pondsConcrete fountains, ponds and birdbaths, from a pint.See the kit
09
Decks & balconiesA flexible waterproof skin over boards, edges and end grain.See the kit
10
Pool decksGrip and color for a deck walked on wet and barefoot.See the kit
11
Garage floorsStop dusting and salt stains with a membrane and a wear coat.See the kit
12
WalkwaysSeal concrete, pavers, brick and flagstone against water and salt.See the kit
02 / The SEMCO system
Prep. Protect. Finish.
Four product families that are made to work together, so the prep, the coat and the finish all bond.
Prep
Every job starts clean. Nu-Lift, Stone Soap or Power Cleaner, chosen by your surface.
- Power Cleanerfrom $27.30
- Stone Soapfrom $27.10
- Nu-Lift Cleanerfrom $23.65
Waterproof
One flexible, water-based membrane for walls, roofs, decks, showers and pools.
- Liquid Membranefrom $26.80
- Fabric Reinforcementfrom $60.15
Color
A water-based stain for concrete and masonry. No acid to mix, neutralize or rinse.
- PreStain Colorfrom $61.90
Seal
A wear coat for surfaces that take traffic: high gloss, matte, or an invisible penetrating seal.
- Titan Shield Glossfrom $33.05
- Natural Shieldfrom $25.30
- Sealer MATTEfrom $40.75
Waterproofing a wall or roof? Prep, then membrane. Coloring concrete? Prep, then PreStain. Seal either one if it takes foot or vehicle traffic.
03 / Liquid Membrane
The numbers behind it.
Stretches up to 1,300% before it fails, so it bridges cracks a rigid coating would split across.
173 PSI at 7 days, building to 234 PSI at four weeks (ANSI A118.10), and 132 PSI after 7 days under water.
Blocks liquid water while still passing vapor, so the surface isn't sealed into a moisture trap.
Water-based and low odor, for basements, showers and crawl spaces with normal ventilation.
Each coat at 15 to 20 mil. Submerged work and bare wood take three coats at about 100 sq ft per gallon.
Five-year standard limited warranty; ten years on non-traffic surfaces, which includes basement walls.
04 / How it works
Done in a weekend.
No primer, no mixing, soap-and-water cleanup.
-
Prep
Clean with the SEMCO cleaner for your surface and let it dry to 3% moisture or less. Press Fabric Reinforcement into joints and cracks wider than 1/4".
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Coat
Two coats, each at 15 to 20 mil, by roller, brush or sprayer. Recoat when it holds no fingerprint, about 25–45 minutes at 72°F. Apply between 50–90°F, out of direct sun.
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Cure
At least 7 days, longer with thick coats or high humidity. If the surface takes traffic, seal it about 2 days after the last coat.
05 / Customer reviews
Real projects. Real reviews.
06 / Before you start
Questions? Start here.
FAQs
Coverage, cure, prep and colors, answered in one place.
Read the FAQsApplication guide
Prep, coats, drying and cure, step by step.
Open the guideColor chart
15 membrane colors, from Semi-Clear to SEMCO Orange.
See the colorsTalk to us
Not sure which kit or prep fits your job? Ask the team.
Contact us07 / From the blog
Worthy reads.
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