Tested for exposure
A membrane left open to the weather must pass the UV test: 1000 hours, keeping at least 40% of its stretch.
AS 4654.1 cl 2.7● System 06 of 12 · Exposed roofs
Roof Waterproofing Membrane: Exposed Roofs & Decks
Membranes left open to the weather: a UV-stable liquid for roofs and box gutters, or a torch-applied sheet with a mineral cap.
AS 4654.1 Class III (101 UV)AS 4654.2NCC Part F1
8products
4CAD details
Up to 25 yrwarranty, depending on the systemwarranty, by system
● The build-up
Eight products, one TDS figure each.
Each layer with the one figure that matters, from its data sheet. Tap a layer to see why it is there.
01
UV-stable liquid membraneACTFLEX 101 UV1.2 mm in 2 coats · 15 L ≈ 7 to 9 m²
Elastomeric acrylic, Class III to AS 4654.1 (Report 254-1). It goes on at 0.92 L/m² a coat. Keep rain off for 72 hours; full cure takes 14 days. Maintenance foot traffic only.
02
Bitumen liquid membraneACTFLEX 901 BUV1.5 mm in 2 coats · 18 kg ≈ 5.1 to 6.8 m²
Water-based bitumen membrane at 2.4 to 3.0 kg/m². Recoat between 8 and 48 hours. Foot traffic after 7 days.
03
Polyurethane membrane and top coatACTFLEX ULTRA TC1.2 mm in 2 coats · 40 kg ≈ 21 m²
Two-part aliphatic polyurethane over two coats of EP250, for trafficked decks. Light foot traffic at 24 hours, full cure in 7 days.
04
Top coat over polyurethaneACTFLEX ATC6 to 8 m² per litre a coat
Aliphatic top coat in two coats, for polyurethane and polyurea membranes only. It is a top coat, not a membrane. Cures in 12 hours.
05
UV top coat over polyureaACTFLEX 747 TC0.4 to 0.5 mm in 2 coats
Aliphatic polyaspartic polyurea top coat, used over ACTFLEX 737 PU and other FORSPEC polyurea coatings. Two coats laid off at right angles; recoat in 2 to 3 hours. Light foot traffic at 24 hours, full cure in 4 to 7 days. Typical values, FORSPEC R&D.
06
Mineral cap sheetFORZAFLEX MINERALE 4.54 mm · Class I to AS 4654.1
Torch-applied APP bitumen cap sheet with a slate granule face (Report 596-1). It is the finished layer of a torch-applied roof. Maintenance access only. Do not coat the mineral surface.
07
Root-resistant torch-on sheetFORZAFLEX RR4 mm · Class I to AS 4654.1
Torch-applied APP bitumen sheet (Report 589-1). A 10 x 1 m roll covers about 9.1 m². Laps are 75 mm at the sides and 150 mm at the ends.
08
Sheet membrane under pedestal decksACTFLEX 1300R1.3 mm · 1.4 x 20 m roll
Butyl sheet for under pavers or decking on pedestals. It must be covered: it is not left open to the weather. Laps are welded 40 mm, with a 150 mm upstand. Flood test at 50 mm for 24 hours.
How much do I need?A 15 L pail of ACTFLEX 101 UV covers 7 to 9 m² in practice at 1.2 mm over two coats.
Calculate →● The rules, in plain English
AS 4654 and the NCC, in short.
No water left standing
Water must reach the outlet and none may stay on the surface. The fall is in the structure, or in a screed under the membrane.
AS 4654.2 cl 2.5.2Apartments under NCC 2025
Concrete roofs on Class 2 to 9 buildings need a 1:80 fall cast into the slab itself. Not for houses.
NCC 2025 Vol One F1D4Walked on, or not
Every system is designed as trafficable or non-trafficable, and the membrane must pass the abrasion test for the traffic it takes.
AS 4654.2 cl 1.5 · AS 4654.1 cl 2.3A plain-English summary, not the standard. Check the current documents for your job, or send us the job.A summary, not the standard. Check the current documents for your job.
● Every product in this system
Exposed roofs: 8 products.
TDS and SDS open straight from the card.
● 3D models
See every layer before site starts.
Each FORSPEC detail is modelled in 3D so the site team sees the build-up for exposed roof & deck waterproofing before anyone opens a pail. Send the job and we model yours.
● On site
Real jobs. Real FORSPEC.
Your job next
Got a job like this coming up?
Send the drawings or a few photos. A FORSPEC rep comes back with the system, the CAD details and a 3D of your job.
Send us your job →● CAD library
Drawn details, ready for your set.
4 standard details for exposed roof & deck waterproofing. Open one to view it and download the PDF and DXF.
● Questions we get
Straight answers, from the TDS.
How much membrane does a roof need?
ACTFLEX 101 UV goes on at 0.92 L/m² a coat, in two coats, to 1.2 mm dry. A 15 L pail covers 7 to 9 m² in practice.
How long before rain or foot traffic?
Keep rain off ACTFLEX 101 UV for 72 hours; it reaches full cure in 14 days. ACTFLEX 901 BUV takes foot traffic after 7 days.
Can you walk on an exposed roof membrane?
ACTFLEX 101 UV and FORZAFLEX MINERALE are for maintenance access only. ACTFLEX ULTRA TC is the trafficable finish.
What top coat goes over a polyurethane membrane?
ACTFLEX ATC, in two coats at 6 to 8 m² per litre a coat. It goes over polyurethane and polyurea membranes only, and it is a top coat, not a membrane.
● Go deeper
Drawings, data sheets, jobs and news.
DrawingsCAD details for this system4 details here, PDF and DXF to download→Data sheetsTDS, SDS and test reportsEvery document for this system→CalculatorACTFLEX 101 UV calculatorArea in, packs out→SpecifySpec clause for this systemClause, drawings, data sheets→ProjectMosman terrace, ACTFLEX 1300RMosman NSW→ProjectChatswood roof, FORZAFLEX torch-onChatswood NSW→Projects4 buildings with these productsWhere this system has been used→NewsEpoxy primer: one coat or two?FORSPEC News→NewsFORZAFLEX torch-on: three sheets, three test reportsFORSPEC News→NewsNCC 2025: eight changes for balconies and roofsFORSPEC News→
● The other systems
Twelve systems. One warranty.
● Not sure it suits the job?
Send us the job. We spec it.
Drawings, photos or a description. A FORSPEC rep comes back with the system, the spec clause, CAD details and a 3D visual within 6 business hours.