RESISTO Joist Guard Self-Adhesive Waterproof Membrane - 4" x 75'
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RESISTO Joist Guard Self-Adhesive Waterproof Membrane - 4" x 75'
Joist Guard is Resisto's self-adhesive membrane for the tops of deck and balcony joists, rim joists and beams. It's an elastomeric SBS bitumen core laminated to a black polyethylene face, and it stops the rot that starts where deck boards trap moisture against exposed wood.
Peel back the silicone release film and press the membrane onto clean, dry lumber with a roller. It self-seals around screws and nails as they're driven through it, so the fastener holes from the decking don't undo the waterproofing.
This 4 in. wide roll suits standard 2 in. joists. Doubled joists, wider beams or a wall-to-deck ledger connection need the 9 in. wide roll instead. It isn't designed for roofing.
Features and Common Uses
- Elastomeric SBS bitumen core stays flexible rather than cracking as the joist moves with temperature and moisture
- Self-seals around deck screws and nails as they're driven through it
- Silicone release film peels off in one piece for a clean, fast application
- Compatible with pressure-treated wood and composite decking
- Made in Canada
Commonly used for:
- Waterproofing the tops of deck and balcony joists before decking goes down
- Protecting rim joists and beams from splash-back and standing water
- New deck builds and joist replacements on existing decks
Specifications
| SKU / Model No. | 10099 |
|---|---|
| Brand | RESISTO (Soprema) |
| Material | SBS modified bitumen core, polyethylene face, silicone release film |
| Width | 4 in. |
| Length | 75 ft. |
| Coverage per Roll | 25 sq. ft. |
| Thickness | 0.6 mm (24 mil) |
| Service Temperature Range | -45 to 85 degrees C (-49 to 185 degrees F) |
| Minimum Application Temperature | -10 degrees C (14 degrees F) |
| Roofing Use | Not rated for roof applications |
Store the roll above 10 degrees C before installing if it's been kept somewhere cold; the adhesive won't grip properly straight out of the cold.
How to Install
- Clean the top of the joist so it's dry and free of dust, sawdust, grease or other debris.
- Cut the membrane to length with a utility knife, adding a couple of inches for any overlap at joints.
- Peel back the silicone release film a section at a time and press the membrane onto the joist, working from one end.
- Go over the full length with a hand roller so it bonds flat with no air pockets.
- Install the deck boards within 48 hours of applying the membrane.
For doubled joists, wider beams or a wall-to-deck ledger connection, use the 9 in. wide roll instead of this 4 in. roll.
Frequently Asked Questions
What size joists does the 4 inch roll fit?
Standard single 2x lumber joists. For doubled joists, wider beams or the wall-to-deck ledger joint, use the 9 in. wide roll instead.
Can I install it in cold weather?
Down to -10 degrees C. If the roll has been stored somewhere cold, let it warm above 10 degrees C first or the adhesive won't grip well.
How long can the joists sit before I put the decking down?
Cover them with decking within 48 hours of applying the membrane.
Does it work under composite decking?
Yes, it's compatible with both pressure-treated wood and composite decking.
Will it still seal once I've screwed the decking down through it?
Yes, the membrane self-seals around screws and nails as they're driven through it.
Can I use it on a roof?
No, Joist Guard is not designed for roofing applications.