A deep dive into the waterproofing systems we install: what each layer does, the specs behind them, and the colors you can choose, straight from the manufacturers’ technical bulletins.
We believe you should know exactly what gets installed on your property. Every spec on this page comes from the manufacturers’ own technical bulletins and third-party code evaluation reports, linked at the bottom of each section.
Desert Crete is a fire-retardant walking deck and roof covering system: a multi-step, polymer-modified cementitious build-up with a fiberglass-reinforced acrylic waterproof membrane at its core. It is the ground-up system we install over plywood on new balconies, walkways, stairs, and roof decks. It is often called a 5-step system for the five coating applications installed over galvanized metal lath. Desert Crete is anything but a newcomer: the system has protected decks across the Western US for decades, and its manufacturer, Hill Brothers Chemical Co., is a family-run California company that has supplied decking and sealer products since 1923. More than a century later, every Desert Brand technical bulletin still carries the tagline “Decking and Sealer Products Since 1923.”
Over prepped 5/8″ minimum exterior-grade plywood and primed galvanized flashing, hot-dipped galvanized metal lath (2.5 lbs per sq yd) is stapled down at 24 staples per square foot, so the cement layers grip the deck structurally.
Polymer-modified cement (Level Max 20/30 with Polymer 550, or Polybase) is troweled into the metal lath, locking it in and creating the structural bed of the system.
The waterproofing heart of the system: fiberglass matting is laid over the base, lapped 2″ over flashings and 1″ at seams, then saturated with Bonder 480 acrylic resin to form a reinforced waterproof membrane.
A second troweled cement application, minimum 1/16″ thick, encases the membrane and builds the wear surface.
Desert Crete Texture is spray-applied with a hopper gun at 30–40 psi, then troweled to the classic slip-resistant knock-down finish.
Two coats of Desert Brand sealer (CMFPS or Master Seal) color the deck and seal the surface. Choose from the CMFPS color chart below.
| Fire rating | Class A roof covering (ASTM E108) and one-hour fire resistance (ASTM E119 per ICC-ES AC39); meets high fire hazard zone standards, incl. SFM 12-7A-4 & 12-7A-5 wildfire exposure |
|---|---|
| Code recognition | IAPMO UES Evaluation Report ER-586 (IBC, IRC, CBC & CRC) |
| Substrate | Minimum 5/8″ exterior-grade or Exposure 1 plywood |
| System weight / thickness | Approx. 3 lbs per sq ft; minimum 1/4″ total base + texture thickness |
| Minimum slope | 2% (1/4″ per foot) for positive drainage |
| Application temperature | 50°F–90°F, dry conditions |
| Manufacturer warranty | Materials warranted 5 years when installed by a Desert Brand Authorized Applicator (1 year otherwise) |
Desert Flex is the restoration counterpart to Desert Crete: a 3-stage overlay of high-quality acrylic resins and fiberglass reinforcement that restores the integrity of an existing deck and increases its waterproofing without tearing the old system out. Tenants and customers lose minimal access during the work, and it can also be used on new concrete.
After a thin troweled prep coat primes and smooths the existing surface, fiberglass matting is laid, lapped 2″ over flashings and 1″ at seams, and saturated with Bonder 480 acrylic resin, bonding a new waterproof membrane onto the old deck.
Two applications of Desert Crete Texture mixed with liquid polymer: a thin troweled coat over the cured membrane, then a hopper-gun coat knocked down with a steel trowel into the slip-resistant finish.
Two coats of pigmented CMFPS color and seal the restored deck, using the same color chart as Desert Crete.
| System type | Acrylic + fiberglass restoration overlay with knock-down texture finish |
|---|---|
| Goes over | Existing sound deck systems: concrete, polymer-modified concrete, pre-sealed magnesite, elastomeric & other systems; also a topcoat over Desert Crete |
| Coverage | Texture ≈200 sq ft per 50-lb bag; Bonder 480 ≈50 sq ft per gallon; CMFPS ≈400–600 sq ft per gallon (pigmented) |
| Application temperature | 50°F–85°F |
| Fire classification | Not published for Desert Flex; projects that need the Class A / one-hour listing get the full Desert Crete system |
| Manufacturer warranty | Materials warranted 3 years when installed by a Desert Brand Authorized Applicator (1 year otherwise) |
When a balcony or deck will be finished in tile, the waterproofing has to live under the tile. Tremco’s Vulkem 350 under-tile system is a seamless, monolithic membrane: a tough-curing liquid polyurethane base coat plus a highly durable low-modulus epoxy top coat, installed beneath thin-set tile. If the tile or grout ever cracks, the rubber membrane underneath keeps water out of the structure.
Concrete is profiled (CSP 2–4), verified at 2,500 psi minimum and below 4.5% moisture; plywood must be well-anchored AC grade. A clean, sound base is non-negotiable for a monolithic membrane.
Structural cracks are ground out and treated, and polyurethane sealant cants are tooled at every wall, post, and joint transition: the spots where decks actually leak.
A 25-mil detail coat of Vulkem 350NF reinforces every cant, crack, and cold joint before the field membrane goes down.
Vulkem 350NF is squeegee-applied at 40–60 wet mils across the whole deck and cures into a seamless rubber membrane that bridges hairline cracks up to 1/16″.
A 10–12 mil epoxy coat is rolled on and flooded with silica sand “to refusal,” creating a hard, gritty bond surface for the tile setting bed.
Tile is set in thin-set over the cured membrane, completing the finished walking surface with the waterproofing sealed underneath.
| System type | Liquid-applied polyurethane base + epoxy top coat, under thin-set tile |
|---|---|
| Elongation (base coat) | 600–700% (ASTM D412); the membrane stretches with structural movement |
| Crack bridging | Retains integrity over hairline substrate cracks up to 1/16″ (1.5 mm) |
| Applied thickness | Base coat 40–60 wet mils (25–40 sq ft/gal); epoxy top coat 10–12 mils (133–160 sq ft/gal) + silica sand broadcast |
| Service temperature | −40°F to 185°F |
| Standards & approvals | ASTM C836 / C957 liquid-applied membrane standards; Miami-Dade County NOA (under-tile assembly); UL 790 fire test method for roof coverings |
CMFPS (Concrete/Masonry Floor Paint & Sealer) is the acrylic color-and-seal coat that finishes both Desert Crete and Desert Flex decks: a low-luster, durable, non-yellowing walking surface. It comes in 12 standard colors, plus plain white and clear.
On-screen colors are approximate; surface texture and application method affect the final color. We bring physical color cards to every estimate so you can confirm your choice in person.
Official manufacturer chart: Desert Brand CMFPS Color Chart (PDF)
We inspect the substrate first, then recommend the right system: free, on-site, no obligation.