QA

How To Do Step Flashing On A Roof

How do you install step flashing on a roof?

Does step flashing go over or under shingles?

Step 4: Begin the weave. With step flashing, you do a little flashing, then a lot of roofing, then a little more flashing, and so on. Each piece of step flashing laps over the shingle below and under the shingle above. The bottom edge of the flashing should extend just below the nail line.

Where does step flashing go on a roof?

Step flashing: Step flashing is best for where the roof face meets a wall, for example, where a dormer projects out of the roof. In this spot, it’s possible that water could flow down the wall and slip past the shingles into the building below.

How much do you overlap step flashing?

Because the flashing is 2 inches wider than the exposure of the shingles, each step flashing piece will overlap the one on the course below by 2 inches. Nail the flashing to the roof deck only. Do not nail it to the wall.

What is the difference between flashing and step flashing?

Step flashing is primarily used against the sides of walls and chimneys. That’s why the term “step” is used in step flashing. You do it step by step by installing a shingle, then a piece of flashing, then another shingle, then a piece of flashing until the wall is completely protected.

How do you seal flashing to shingles?

Seal the seam between the cap and step flashing with urethane roofing cement or silicone caulking compound, as shown at right. If you are working with valley flashing, lift the edges of the surrounding shingles, and spread roofing cement on the flashing about 6 inches in from the edge of the shingles.

Should flashing be installed on top of shingles?

All shingle manufacturers require step flashing at sidewalls for both asphalt, wood and slate. Instead of installing the step flashing between shingles, the flashing rests on top of the shingles. It’s not unusual to see sealant installed when sidewall flashing is missing. Sealant will eventually dry, shrink and crack.

Does flashing go over or under tar paper?

Installing roof drip edge flashing properly The best way is to install the roof drip edge only along the eaves first, then place ice-and-water barrier (in the snowbelt) or felt paper (underlayment) over the drip edge. This lets any water that gets on the roof run down the underlayment and over the drip edge.

Do you need soakers on a roof?

Using standard lead roll Lead soakers are an integral part of virtually any tiled roof. Not only do they prevent any water ingress at the abutment to a wall, but also provide a professional aesthetic. Using standard lead rolls to form soakers can be time-consuming.

Do you need step flashing?

Step flashing has been required for asphalt shingles at roof-to-wall intersections as far back as the 1986 CABO. Step flashing ensures that any water that migrates underneath a shingle will still end up on top of the flashing that is covering the shingle below. The water can then drain away safely.

Does step flashing go behind house wrap?

Wrap roof paper up the wall to backup the step flashing. Five inches up the wall is good for 4-inch step flashing. It should be high enough for visual verification that it was done. Cut the house wrap so that the roof paper can be tucked underneath.

Do you need to caulk roof flashing?

Roof flashings can be made from thin metal, rubber, and a few other materials. It’s okay to use caulk and roofing cement as a last resort to make a temporary leak repair, but don’t allow a roofer to convince you they’ll work for the long term.

Does flashing need to be sealed?

The flashing’s design is meant to prevent as much water from getting inside the seams between sheet metal layers as possible. After the sheet metal flashing has been installed, applying proper sealant is critical to its success.

What do you seal roof flashing with?

As long as the flashing has been installed properly, you can repair a leaking seam using simple roofing cement in most instances. Simply push the seam back down and secure it in place with screws if necessary, and then apply roofing cement around all the edges of the flashing for a watertight seal.

Is step flashing better?

Step flashing offers far better protection from leaks, because even if a single piece of step flashing fails, the water just hits the next lower piece. That flashing directs the water onto the shingle and the water drains down the roof.

Should shingles overhang drip edge?

Asphalt shingles should overhang the exterior edge of the drip edge by ¼ to ¾-inch. Check local building code for drip edge requirements prior to the start of your roofing project.

Can roofing felt be used as flashing?

Roofing felt: Felt should only really be used alongside another material for flashing as the felt will not offer full waterproof protection and is not as strong or durable as some of the other options listed here. Rubber: Rubber is flammable, so can pose a serious fire risk.

What goes down first drip edge or underlayment?

According to most building codes and manufacturer recommendations, the drip edge should be installed beneath the underlayment along the eaves of the roof. But over the underlayment along the rake edges of the roof. Understanding the proper way to install the drip edge will only get you so far.

Does roofing felt go over or under drip edge?

1 Answer. It depends on where the drip edge is. At the side, or gabels, of a roof, the drip edge goes over the roofing felt. At the bottom of the roof, the drip edge goes under the roofing felt.