If your roof has a T or an L-shape, or if there is a dormer or bay window, two roof sections may run perpendicular to each other. A valley is a line where the two perpendicular slopes meet one another.
When it rains, water that falls on the slope of the roof section flows down to the valleys, which means that a valley has to be able to handle large volumes of water. When a copper or lead valley is damaged, it can result in severe leakage to the interior of the building.
It follows, then, that materials that cover the valley should be waterproof and properly installed. These materials are usually copper, zinc, aluminium, or lead. You should also make sure that you inspect the valley at least twice a year to ensure that the covering materials are in the best possible condition to prevent leakage and damage to your trusses or ceiling.
Keep reading to learn more about the different types of lead and copper valleys and their importance to the structural integrity of your roof.
Roofers Dublin roofing specialists.
Copper and Lead Valley Repairs and Installation
There are, in essence, two types of roof valleys: open and closed.
Closed Roof Valleys
Also called a California cut, a closed valley is when the valley is covered by the primary roofing material of the higher slope. It is important to fit the shingles or roofing material of the lower slope first and then to cut the shingles of the higher slope that it overlaps the valley completely.
When it rains, the water then flows from the higher slope over the valley onto the lower slope. This is a much more affordable option than an open roof valley, but it is important to do this right, as water can flow in underneath the top slope roofing material and cause an accumulation of mud and water.
Closed roof valleys also tend to leak easier than other methods, so if this is the method you prefer, make sure that that you get the help of a professional.
Open Roof Valley
In this case, the valley is not covered by tiles or any roofing material. This design consists of a shield layer that keeps ice and water out that is covered by a metal flashing. Before applying the self-adhesive shield, it is important to clean the open valley thoroughly and remove any mud and debris that may be lodged between the two slopes.
The metal cover can either have a V-design that is bent to the angle of the valley between the two slopes or it can have a W-design, which means that there is a bump in the middle so that water can’t flow in underneath the roofing material of the slopes.
It is important to close the openings on either end of the valley to prevent insects or debris from entering beneath the metal valley covers.
Which Type is Best?
Closed roof valleys have a number of benefits, the biggest being affordability and aesthetic appeal. Since the roofing material ‘flow’ from one slope to the next, it allows for uniformity and requires no additional roofing materials. It is, however, a riskier and maintenance-intensive type of valley.
Open roof valleys are much more durable and can handle larger quantities of water. It also requires less maintenance and cleaning than closed roof valleys. If you live in an area that gets a lot of rain, copper valleys or lead valleys may be the better option. It is also a more cost-effective one in the long-run as the copper or lead covers are easy and affordable to replace. With a little experience, you may be able to install the valley yourself.
Roofers Dublin can be contacted on 1800 911 007 for all your lead and copper valley needs and also to conduct roof flashing repair.