When considering how to shingle a valley with architectural shingles, you must take into account their thickness and reduced flexibility. Laminated shingles are more liable to create bumps in woven valleys. Often, they are too thick to be woven at all.
How far should shingles overlap a valley?
Shingles should overlap the edge of the liner panels by at least 6 in., and at least 3 in. of metal should be exposed on each side of the valley center for appearance and water flow. Shingles can be trimmed and dubbed before they’re nailed in, or run long across the valley and trimmed and dubbed after.
What side of valley do you shingle first?
Each end shingle strip should have the upper corner trimmed and set in a bead of roof cement. NRCA recommends shingles first be installed on the valley side with the lowest slope or shortest distance to the ridge. If all conditions are equal, either side may be installed first.
Can architectural shingles be racked?
For Three Tab Shingles… the racking method is acceptable, however, it is not the preferred method of installation because of the possible installation problems and damage if proper precautions are not followed. All other shingles (laminated or designer shingles)… the racking method is NOT acceptable.
Can you weave a valley with architectural shingles Related Questions
Which style of valley are architectural shingles not allowed to be used in?
Because of this, woven valleys are not recommended by most laminate shingle manufacturers. Having woven valleys installed may void your limited warranty. Woven valleys also do not save the roofing professional in time or materials over closed-cut valleys.
What is the disadvantage of a valley roof?
Leak Risks Increase. Hip and valley roofs have multiple valleys that help lead rainwater flow into gutters and downspouts. However, properties with mechanically-fastened or fully-adhered systems such as EPDM roofs are at risk of heavy leaks.
Do roof valleys need flashing?
One of the most important aspects of roof valley installation is the flashing. Valley flashing is used to seal off the area where two roof slopes meet, and it helps to prevent water from leaking into the home.
Should valley shingles be sealed?
Valleys should be carefully sealed along the entire length. To help prevent water entry at these vulnerable points, install a self-sealing bituminous membrane or the equivalent along all valleys and properly integrate this membrane into the adjoining roofing materials.
Can you shingle over 3 tab with architectural shingles?
In most cases, you can apply a second layer of three-tab shingles over an existing roof that features three-tab shingles without having to tear off the existing roof. However, you cannot apply three-tab shingles over architectural shingles.
How do you lay the first row of architectural shingles?
Lay one row of shingles, starting from the lower left corner of the roof. This row should project half an inch (1.27 centimeters) over the eaves. Nail down the shingles as you go along. Lay the next row of shingles, directly on top of the first row, making the row two tiles thick.
How many shingles do I need for a valley?
Order two extra shingles per linear foot of valley to account for the overlaps and cutoffs. On a 16-ft. valley, you would need 32 shingles or roughly one extra bundle.
Do you overhang shingles over drip edge?
Shingles should be installed over the drip edge a minimum of 3/8” (9 mm) at both the eave edge and the rake edge. If the drip edge extends… out from the rakes and eaves (typically called DL Style or D Type), the shingles may be installed flush with the drip edge.
Can you have 2 layers of architectural shingles?
In most states, you’re only allowed to have 2 layers of shingles on a roof for fire safety reasons. However, you’ll still see roofs that have 3 or 4 layers today. If you already have 2 or more layers, a contractor will recommend a full replacement.
How much should architectural shingles overlap?
Overlap each row by two inches. Sides should be overlapped by four inches. Use a bare minimum of fasteners; just enough to hold the underlayment in place for the next step. Make sure that you apply one layer of underlayment over the metal drip edge along the eaves.
Do you start at the top or bottom when shingling?
To lay out the design for the shingles, begin at the bottom of the roof and place a tape measure ¬Ω inch from the edge of the roof to ensure the shingles overhang the drip edge. Mark 12 inches up on the roof for the first course of shingles, then mark every 5 inches all the way up the roof to set your reveal.
What is the life of a roof with architectural shingles?
The different asphalt shingle roof types and their expected lifespans are: 3-tab shingles: The cheapest asphalt shingle type lasting between 15-30 years. Architectural shingles: Also called dimensional shingles, these asphalt shingles are mid-range priced and last between 20-30 years.
How do you keep architectural shingles straight?
A chalk line can keep your line straight over long distances and large areas. A chalk line can help eliminate short exposures, waviness and additional antithetical issues. The first step in roofing is always to install the underlayment and any additional weather shields.
Why do architectural shingles leak?
The transitions between sections of a shingle roof are sealed with metal roof flashing. For instance, flashing is frequently positioned around chimneys, the edges of skylights and where a dormer meets the roof. Over time, the caulking under flashing can dry out and crack and the nails can loosen, resulting in leaks.
Why do roof valleys leak?
Often when your roof valley is leaking, the true cause is the membrane or underlay beneath your roofing materials. As these membranes are often not expected to last as long as the tiles above, they can become damaged far sooner and lead to roof leaks and other issues.
What is a valley flashing that Cannot be seen called?
Closed valleys are those in which no flashing is visible in the valley. In a true closed valley, the roof-covering material is continuous across the valley and protects it from moisture intrusion.