Permeable Seamless Roof Surface

With the new seamless barrier.

Permeable seamless roof surface.

The new standing seam metal roof is to be installed over the existing 1x4 skip sheathing so no solid roof deck. Permeable surfaces also known as porous or pervious surfaces allow water to percolate into the soil to filter out pollutants and recharge the water table. From the top down there are four layers to permeable paving. Regardless of your roofing underlayment choice your insulated roof assembly will not dry to the exterior unless the roofing is vapor permeable.

Seamless roof coating solutions take care of this immediately though in many cases. Other types of roofing including cedar shingles and concrete tile roofing are fairly permeable. But the attic floor air seal is terrible there s a huge attic stair that leaks like a sieve. The top layer is the actual paving material.

In this particular job the roof is vented. Any moisture driven up from the attic will condense on the underlayment underside. After all water can gather under an existing roof surface and then over time erode and ruin the roofing components underneath the surface layer. 3 roofing liquid applied membranes seamless roofing solution content 04 sika liquid applied membranes lam 06 applications of sika liquid applied membranes 10 sika s global technology and production competence 12 cool roofs with liquid applied membranes 14 technologies products 20 lam systems for exposed roofs 22 lam systems for green roofs 24 lam systems for refurbishment of old roofs.

Asphalt shingles are a little bit permeable in windy conditions but not very. Impermeable impervious surfaces are solid surfaces that don t allow water to penetrate forcing it to run off. These steel purlins are also used in steel sided buildings that have osb wall sheathing. Even smaller roof leaks can lead to bigger problems if they are left untended.

Consider permeable paving in large walkways or driveways and make sure that a 6 inch gravel bed is immediately below the porous material.