While polyurethane does have its strengths related to its fairly low price silicone is by far the superior choice when choosing a chimney sealer.
Caulking for chimney flashing.
Polyurethane has a tendency to break down and has lifespan at best half that of silicone.
Here is how you do it.
Fit an 8 inch 20 3 cm piece of square step flashing over the chimney s front corner.
Loctite pl s30 polyurethane roof and flashing sealant is a premium quality commercial grade sealant developed especially for forming permanent water and weatherproof seals in all exterior gaps and joints.
In the second layer more sheet metal is inserted into the chimney mortar joints and folded over to cover the first layer.
Put a layer on the edge of each piece of flashing.
Place a small drop of caulk where the roof and chimney meet at the chimney corner.
Like any other caulking job you want to push the bead not pull it.
Place the step flashing over the caulk and onto the chimney.
Effective roof flashing around a chimney includes two layers.
Getting the right sealant on your flashing is the best bet.
Place the flashing or boot onto the plumbing vent so the base is resting on shingles.
Install shingles as normal up to the base of the plumbing vent.
Momentarily lift the boot and apply sealant to hold the flashing in.
You don t have to make it look nice you just need to fully fill the gap.
Seal the problem seams with roofing caulk using a standard caulk application technique.
Materials required 26 gauge galvanized sheet steel for prefabricated pieces drive in expanding anchors galvanized coil stock galvanized front base flashing galvanized step flashing polyurethane caulk self adhering roofing membrane ice and water barrier.
You can t use too much so get as much as you can in there.
This sealant is elastic and remains flexible to expand and contract with construction material movement to protect and retain the original.
Set the flashing aside.
Installing a roof plumbing vent is typically an easier task than flashing a chimney.
You want to squeeze it into all the nooks and crannies you can.
