Table of Contents
How To Install Metal Roof Over Shingles 3.1 STEP 1: Get a precise measurement of your roof surface. 3.2 STEP 2: Lay down roofing felt over the entire roof. 3.3 STEP 3: Start putting the metal panels into place. 3.4 STEP 4: Install rubber or foam closure strips. 3.5 STEP 5: Attach the ridge cap.
What is the best way to install a metal roof over shingles?
The first is to apply an approved underlayment over the old shingles. This is the fastest way to install but it doesn’t provide the flattest surface for metal roofing installation. The second way is to install 1×4 purlins over the shingles. This is more expensive but will also be higher quality.
Can metal roofing be installed over asphalt shingles?
The short answer is yes, you’re able to roof over your old asphalt roof with a new metal roof under the right circumstances. You’ll be able to save up to 25% in labor costs by not tearing off your old asphalt roof, installing new underlayment, or the fees to dump the old roofing materials.
Do I need furring strips under metal roof?
When installing a metal roof over an existing roof, insulate the spaces between the wood strips with rigid insulation to prevent condensation before installing the roofing. You also need to add furring strips. Twenty-four inches is a common spacing of furring strips for a metal roof.
Can you put metal roof over shingles without furring strips?
One option for installing a metal roof over shingles without furring strips is to use a cross-batten style. A cross-batten technique involves laying down vertical battens first. Next, the battens attach through the roof deck to your rafters. Finally, your horizontal battens are placed.
What type of underlayment do you use on a metal roof?
The traditional and most common material used for roof underlayment on a steep-slope metal roof is non-perforated, asphalt-impregnated felt underlayment. There are several types of felt underlayment including both organic reinforced and inorganic reinforced.
How do you vent a metal roof over shingles?
To vent the roof, holes are cut in the old roof (Detail 1) above the soffit, which pulls air through the soffit vents underneath. Cool outside air then travels under the shingles to the vented ridge (Detail 2), pulling out moisture and heat.
Does a metal roof need to be vented?
Energy Savings Proper ventilation is needed to ensure the energy efficiency a metal roof provides. An effectively ventilated metal roof helps to prevent energy waste and excess cooling cost that can occur when attic heat builds up with.
What are the steps to installing a metal roof?
Step-By-Step Step 1: Measure the roof area. Step 2: Order the materials. Step 3: Remove the old roof. Step 4: Add insulation. Step 5: Install the eave flashing. Step 6: Metal Roof Installation: Add metal panels. Step 7: Add the flashing to the roof. Step 8: Finish.
How far apart should rafters be on a metal roof?
Both 16 inches and 24 inches are common measurements for rafter spacing.
Are furring strips necessary?
Whether it’s the ceiling or the walls, furring strips are essential to ensuring that you’ll always get a flat and smooth surface when the project is complete. When applying furring strips to your walls, they will have to be directly screwed or nailed into the wood or concrete wall.
Are purlins required for metal roofing?
Do all roofing projects require purlins? No. We do recommend it, however.
Do you have to put plywood under metal roof?
As long as the interior of your roof is protected from moisture accumulation, underlayment is not required, though homeowners planning to insulate their house heavily may choose to install plywood to protect their investment.
Where do you put the screws on a metal roof?
And most U.S. metal roofing manufacturers say that you should put screws into the flat, because this location offers a solid wood surface just beneath the metal panel, resulting in a safer, tighter, more secure seal.
Do you need a vapor barrier under a metal roof?
To avoid condensation buildup with your metal roof, you will need to have a moisture barrier in place. It depends on air temperature, water vapor near the metal panels, the prevalence of warm air in and around your roof assembly, and other conditions.
Do you need to put tar paper under a metal roof?
Metal roof underlayment is an important component of a metal roofing system. Some might choose to skip using underlayment to save money. However, the metal roof underlayment acts as an added layer of protection. The short answer is yes, your metal roof does need underlayment .
What goes under a standing seam metal roof?
Underlayment is usually a felt (15 lb, 30 lb, or synthetic) material used over your decking to provide additional protection. That makes it a crucial component to your metal roof. For your standing seam metal roof, your underlayment will be a self-adhering, high heat ice and water shield.
Should metal roofs have ridge vents?
Ridge Vents for Metal Roofs Ridge vents are a very effective way to promote proper attic ventilation and are commonly used on shingle roofs and roofs covered with other materials. Ridge vents are becoming more popular for metal roofs, as well.
How much should a corrugated roof overlap?
An overlap of 150mm is often recommended for roofs with 10° pitches, whilst 300mm is recommended for 5° pitches. Always allow for an overhang of at least 60-70mm so that water can run off without coming into contact with rafters or purlins, which can lead to damp and structural weakness.
