Old houses often develop cracks between the chimney and the
roof. In this article, the cracks between the chimney and a metal roof are sealed
using roof cement. This is a perpetual maintenance issue and should be checked
every few years. Here's a list of items you will need.
- Roof cement (preferably in a tube, not can)
- Extension ladder
The first step is to access the roof using an extension ladder,
preferably on a warm day. If you are using roof cement, I recommend using the
tube package which fits your caulking gun. The gun only requires one hand, whereas
the roof cement in a can requires two hands, to hold the cement and a trowel.
The cement in a can may be less expensive, but we would recommend against this,
especially on a tin roof like this one.
First examine the area between the brick and the roofing, looking
for small cracks (Fig. 1), separations (Fig. 2), and loose areas. These are
caused in part by deterioration of the old cement and the different thermal
expansion properties of the chimney and the roof.
Using the caulking gun, force ample amounts roof cement into
the cracks (Fig. 3). Apply a liberal amount in all areas (Fig. 4).
On the vertical areas it may be necessary to smooth the excess
(Fig. 5) cement using a trowel.
After the chimney is sealed, look to the plumbing vents (Fig.
6) and don't overlook the stack of the flue (Fig. 7).