We will look at how to flash a metal roof against a wall.
Flashing the seam where a metal roof meets a wall is vital to roofing construction because it keeps water out of the structure and prevents costly damage.
Flashing is a waterproofing membrane between a roof and a wall to deflect water from the building.
It is combined with roofing underlayment and sealer to produce a waterproof seal and is often constructed of aluminum or galvanized steel.
Metal Roof Wall Flashing
Flashing must be installed correctly to avoid leaks and other damage to the roof.
Essential components and installation methods for flashing metal roofs against walls are covered in this article.
Flashing a metal roof against a wall calls for a few essential supplies. Metal flashing, roofing underlayment, and caulk all fall within this category.
• Metal Flashing
Flashing is used to seal the joint between the roof and the wall and is commonly constructed of aluminum or galvanized steel. L-shaped, J-shaped, and step flashing are just a few available forms.
• Roofing Underlayment
Under the metal flashing, this layer acts as an extra barrier against water damage. Felt or synthetic material saturated with asphalt is the usual material of choice.
The joints and gaps between the metal flashing and the wall are sealed with sealant. A caulk gun is used to apply a silicone or butyl-based substance.
How to Flash a Metal Roof to a Wall
You must follow several procedures to install metal flashing against a wall properly.
Step 1: Prepare the Surface
Wall surface preparation is the first stage in installing metal flashing. This is vital in ensuring the flashing is put correctly and can keep water out of the structure.
Cleaning the area to be flashed and removing debris, dirt, or other pollutants is integral to surface preparation. You can use a pressure washer or a wire brush to scrub the wall and remove flaking paint, dust, or other debris.
In addition, before installing the flashing, the wall should be fixed for any damage, such as cracks, holes, or other imperfections.
Before installing flashing, ensure the wall surface is dry, clean, and in good shape. This is necessary to avoid water leaks and penetration by securely attaching the flashing to the wall.
Step 2: Install the Underlayment
After the wall is prepared, the roofing underlayment is put in place. This is an extra barrier against water intrusion installed beneath the metal flashing.
Felt or synthetic textiles impregnated with asphalt are common construction materials. The underlayment is rolled out on the wall, starting at the bottom and working your way up.
If pipes or vents are in the way, you’ll need to trim them so that it fits around them.
The underlayment must be laid so that it overhangs the wall by at least 2 inches and is then securely connected to the wall using nails or glue.
By applying down the underlayment, you can prevent water from penetrating the wall and create a flat surface for the metal flashing to adhere to.
Step 3: Install the Flashing
After the underlayment has been installed, the metal flashing may go up. The bottom of the wall is flashed with an L or J form, while the top is flashed with a step flashing.
The L-shaped and the J-shaped flashing are used to protect the wall’s edges and corners, and the step flashing, which covers the remaining space, is utilized.
The flashing must be installed and overhang the wall by at least 2 inches to preserve the underlayment.
To properly install the flashing, it must be trimmed to fit around any pipes or vents and then fastened to the wall with nails or screws. For efficient water shed and prevention of water penetration, the flashing should overlap by at least 2 inches.
Step 4: Seal the Joints
Water may be kept out of the structure by ensuring all the gaps and cracks between the metal flashing and the wall are sealed.
Typically, a silicone or butyl-based sealant is used and applied using a caulk gun; this sealant is explicitly made for use on metal.
These sealants are impervious to the ravages of time and the sun, and they offer a seal that is both flexible and resilient, allowing the building to expand and contract without breaking or leaking.
The sealant must be applied in a continuous bead without gaps or voids to ensure the joints and seams are adequately sealed.
Once applied, a putty knife may be used to smooth out the adhesive, and the roof can cure fully before any more work is done.
Step 5: Finish the Installation
The last step is crucial when putting metal flashing against a wall since it guarantees the flashing is well-protected and presents a pleasing aesthetic.
An essential step in preventing water and other debris from entering the structure via the flashing is to install a metal cap or trim over the top of the flashing.
Whether a cap or trim, this finishing touch should be crafted from the same material as the flashing and fastened using screws or nails.
The installation is incomplete until the flashing is painted or coated to match the wall. This makes the flashing less obvious and completes the aesthetic of the roof.
If you want your paint or coating to last, it must be good quality and made for metal surfaces.
Also, remember that even once the installation is complete, you’ll still need to keep an eye on the flashing to ensure it’s doing its job. Maintaining the roof’s flashing is an excellent way to extend the roof’s life and cut costs.
In conclusion, flashing the seam where a metal roof meets a wall is a crucial step in roofing construction that significantly reduces the likelihood of water seepage and subsequent structural damage.
Protecting the roof from leaks and other damage is essential by correctly installing flashing and the roofing underlayment and sealant.
Sealant, roofing underlayment, and metal flashing are the primary tools for flashing metal roofs to walls. Proper installation methods include surface prep, underlayment, flashing, joint sealing, and final installation.
If you are unclear about installing flashing, it is highly recommended that you seek the advice of a professional roofing contractor.