This intersection is critical.
Water resistant membrane air gap under siding.
The exterior face of the foam sheathing is typically the water control layer for the assembly and we need an air gap between it and the stucco cladding to drain the rainwater penetrating the stucco downwards and outwards preventing the build up of hydrostatic pressure.
Flashing membranes are now widely used to prevent water leakage around windows and doors and other trouble spots on walls.
A way to escape sounds logical but couldn t the gap become an open invitation for termites and exterior vapor as well.
Installing a strip of self healing bituthane membrane like ice and water shield under the siding at the bottom of the wall may be a worthwhile investment.
A 1 inch air gap is needed behind brick veneer as required by the 2009 international residential code irc baechler et al.
Typical housewraps provide only a water resistant barrier which can trap water behind claddings.
Hardiewrap weather barrier is installed over the sheathing beneath the exterior siding to reduce water and air infiltration.
The layer beneath the siding the water resistive barrier or wrb is what will protect the plywood or oriented strand board osb sheathing from any water that sneaks in.
Once you staple or fasten a membrane to a wall and pinch it between the siding and the sheathing most membranes leak.
That gap in a rain screen doesn t need to be significant just enough for water to drain and air to rise.
Sold as flashing tape flexible flashing and peel and stick window flashing these narrow rolls of rubberized asphalt membrane can solve many flashing problems if installed correctly.
The argument for it that it allows inadvertent moisture from interior vapor rain etc.
Many builders have turned to huber s zip system sheathing a type of osb with a coating of resin impregnated kraft paper.
View the test results.
How much of an air gap do you need.
Water holdout air penetration resistance and tear resistance.
The tent won t leak until you touch it from the inside with your finger.
Carefully detail the area at the bottom of the wall where the sill connects to the foundation.
Same as with osb 3 8 inch.
Should wood siding necessarily have an air gap between it and the wall sheathing behind it in a cold climate.
It s a little like an old fashioned single wall tent.
Building america recommends a gap of at least 1 16 inch behind lap siding and a drainage space of inch between stucco and plastic house wraps to control liquid phase water penetration.
If the weather barrier is tightly attached as in the case of a peel and stick membrane or is part of a rigid board product building scientists say as little as 1 16th gap provides a capillary break that will let liquid water drain out.
Hydrogap s drainage space removes 100x more bulk water while acting as a water resistant barrier.
