Chimney waterproofing in Bryceville by local experts

Waiting after the joints are repointed

New mortar in a joint is still hardening and still giving off water for days after it is placed. Coating it too soon can interfere with that cure and lock the moisture in. BIA's pre-coating checklist sets a floor of 72 hours for freshly repointed mortar and repaired sealant joints, and the maker of the repellent we use sets the same interval after tuckpointing or other repairs.

On a chimney that has just been repointed, treatment is therefore booked as a separate visit. Writing the cure period on the estimate keeps anyone from spraying on the same afternoon the trowels are put away.

Applying from the bottom up

On a vertical face, the maker's directions for our product start at the bottom and work upward, using a low-pressure sprayer with a fan nozzle or a roller. Each pass floods the brick until a little excess runs down below the wet area, and a second wet application follows within minutes, before the first has soaked away. Starting low means any run-down falls onto brick that has not been treated yet, instead of streaking across finished work. Each face is completed in one continuous session so there are no lap marks where one day's work meets the next. Corners and the edges of the crown are cut in by brush where the spray cannot reach cleanly.

Old sealer on the brick

Sealer applied in the past may still be on the brick, and a new treatment has to work with it or replace it. According to BIA, penetrating repellents are typically incompatible with film-forming coatings already on the brick, and putting one over the other can lead to clouding or poor penetration. Signs of an old film include a gloss, a whitish haze or patches that have peeled away. When we see those, a small test tells us more, and removal is listed as its own step, done to the old product maker's directions and with the removal products disposed of properly.