Keeping Water out of the Top of Brick Walls

o2barockstar

I recently purchased an old house to be used as a rental. It's a brick house with a flat roof and the brick walls extend about 2 feet higher than the roof. The previous owners put on a new roll out type roof but the "rubber" material used on the roof only covers half of the top part of the brick walls that surround the roof (the walls are 10 inches thick and the roof material only covers about 5 inches across the top of the walls). Water runs down through the bricks and inside the house so I need to make sure the top part of the walls are protected from water. Is it better to try to purchase Couping Stones and cover the tops of the walls (the walls are 10" thick and at 180 linear feet of wall, this option might get expensive) OR can I have someone make me a "wall cap" out of some aluminum or gutter material and then secure it to the top of the walls somehow OR can I have them just use the "rubber" material they used for the roof in the first place and make a "wall cap", overlap it 6" inches on both side of the wall. I don't want to spend a fortune but I also don't want to have to worry about this problem at some later time.

concretemasonry

You can put a cap on the parapet walls. Parapet walls are very common spots for water penetration.

Even with a "cap" you need it eo extend down on both sides. With a wind, it is common for water to be forced up as much as 6" above the bottom of the cap. This area is also a point of rapid deterioration, which can really be costly.

with the detail you explained, it sounds like an amateur roofing patch-job and you should also look at the joint between the "rubber" and the real roofing.

Ed the Roofer

It sounds as if they did not do a good quality job of terminating the roof flashing material on the sides of the parapet walls.

It very well could have gone up higher than they installed it, although the specifications they provided may have met the "Minimum" height requirements.

An aluminum coping cap could be fabricated, but their is an art to installing an architectural sheet metal coping cap in place with proper cleats and splice plates and multiple possibilities of alternative installation methods.

The clay tile coping caps are an expensive option, but the flange that protrudes downward over the interior parapet walls will more than likely not come down far enough vertically to counter-flash the existing height of the current wall flashing materials.

Do you per chance have any digital photos that you could upload onto this forum for a better perspective of the situation and if possible, also lay out a tape measure vertically for a reference frame of view point?

Ed

Tscarborough

Retrofitting correct parapet flashing is never cheap or easy, although doing it correctly during new construction is pretty simple and straight forward. A metal cap is your best bet, but as noted, it has to be done properly or you will just be wasting a lot more money with poor results.

ncgrogan

Two ways to fix it. Install copper laminate through wall flashing and extend it over top of the term bar/wall flashing several inches. Then put your coping stones on. The stones will leak just like the brick/unless its a really a dense stone material, but most Ive seen around here are just cast concrete.

2nd option like others said is to put a metal coping cap on. I would still put 20mil pvc under the cap in case it leaks. We like 1 inch standing seams not lapped seams. Also most building codes require an ANSI/SPRI type detail which gets pretty specific about hem and cleat sizes. Pick up a SMACNA manual. They are only about a $100 and well worth it.