Q – I’m using your Poly Wall® WindowSeal® on a few Multi-family projects, they’re kicking us back on submittals using a NP1 caulking. Apparently it’s too corrosive for this product. Do you have any recommendations on sealant and caulking that will be safe on the asphalt base?

A – Poly Wall® has the following suggestions for selecting sealants and caulks compatible with Poly Wall’s asphalt-based flashing and tape products:

Polyurethane Sealant and Caulking: Two-part polyurethanes are acceptable to be used under the WindowSeal® asphalt flashing tape, as long as they are fully cured according to manufacturer’s recommendations and specification. Single-component urethanes are generally moisture cure; and, when covered by an asphalt flashing tape, will not cure. Both single- and two-part polyurethanes can be used on top of the WindowSeal® tape without affecting the integrity of the flashing tape.

Polysulfide Sealant and Caulking: They are not compatible with WindowSeal®; even the residue can cause severe damage to the integrity of the WindowSeal® asphalt component.

Butyl Sealants: Are acceptable as long as they are fully cured according to the manufacturer’s specifications and recommendations. All solvent must be evaporated completely.  Butyl sealants can be used on top of the membrane.

Silicone Sealants and Caulking: Silicone can be used on top of the WindowSeal® flashing without affecting the integrity of the tape; however, a pull test is suggested to ensure adhesion to the WindowSeal® polyethylene film. Silicone under the flashing tape may only allow moderate adhesion for WindowSeal®. A test patch is recommended prior to the WindowSeal® installation over silicone.

Q – How fast can your 2300 Liquid Wrap be spray applied?

A – You should budget an application rate of 375-750 S/F per hour and lean toward the upper end of that range if you have an experienced and skilled applicator at the end of the line.