What built-up roofing involves
Alternating plies and bitumen built into one thick assembly.
Heavy, redundant and long-lived where the structure carries it.
What matters on built-up roofing
Drainage before material
The first question on any low-slope roof is where the water goes. Ponding is what kills membranes, and a roof that holds water for days after a storm will fail early regardless of which sheet is on it. We look at the slope, the drains and the terminations before we talk about material.
Seams and terminations
Field failures on commercial roofs are rare. Failures at seams, curbs, drains and the parapet edge are common. A hot-air welded seam that has been probed is a continuous sheet. Anything taped or glued and unverified is a scheduled leak.
How the system goes together
How long a bead of sealant lasts
Roof sealant is a consumable. In this climate, with the ultraviolet load and the temperature swing, a good product stays flexible for a handful of years and then shrinks, crazes and pulls away from one side of the joint. That is normal and expected behavior for the material.
Design so sealant is a backup
Every joint that matters should shed water by its shape, with the sealant there as a second line. Where sealant is the only thing standing between water and the deck, somebody has signed you up for a maintenance visit every few years.
Ask what is holding a repair together
If the answer is caulk, ask again.
Ridge vent against box vents
A continuous ridge slot pulls air along the entire peak, which is why it outperforms a row of box vents on most houses. Box vents still win in specific situations: a hip roof with almost no ridge to cut, a roof broken into separate attic spaces that do not share air, or a low ridge where a slot would sit under drifted snow all winter.
Never mix the two on one attic
Put both on the same space and the ridge pulls its air from the nearest box vent instead of from the soffit. The attic barely moves and the roof looks correctly vented from the driveway.
What we check
- Field condition and granule loss
- Valleys, ridges and every transition
- Penetrations and their flashing
- Gutter and fascia condition
How we approach it
Look first
We get on the roof and read what is actually happening before quoting anything.
Say what we find
Photographs and a plain explanation, including when the answer is that you do not need us yet.
Built in sequence
Crews we hire and run, working the right detail in the right order.
Leave it clean
Magnet over the yard, container gone, walked with you.
Fog that never burns off
Valley fog in the cold months sits low and holds. It puts a film of moisture on everything without registering as precipitation, which is why a homeowner can swear it has not rained in three weeks while the roof has been wet the whole time. Organic debris in a valley stays soft and packed instead of drying out and blowing clear.
Where that shows first
Under the bottom course at a wall, and in the seam where a porch roof ties into the main body of the house.
Chimneys and the winter melt
Masonry sits colder than the roof around it and snow banks against the uphill side. Meltwater runs down the brick and looks for a way in. Step flashing, counter flashing tucked into a reglet cut, and a cricket behind a wide chimney are what keep it out. A bead of sealant across a chimney base is a temporary measure that somebody will be redoing in two winters.
Old mortar makes it worse
Where the joints have gone soft, the water gets into the masonry itself and the flashing is only half the job.
Where roofs go wrong
The shortcut we see most
A membrane laid over wet insulation because tearing off would have cost a day. The roof looks finished, the moisture stays underneath, and the sheet fails early from below.
What good looks like instead
Moisture surveyed, wet sections cut out and replaced, drainage corrected, then the membrane installed and its seams probed.
Signs worth a look
- Ponding water still standing two days after rain
- Seams that have lifted or opened at an edge
- Blisters or ridging across the field
- Interior staining near drains, curbs or the parapet
What to expect
Scheduling around your operation
Most commercial work can be staged so the disruptive part happens when the building is quiet. Tear-off noise, crane or hoist time and material deliveries all get planned against your hours rather than ours.
What the roof survey covers
Before specifying anything we survey the existing assembly: slope and drainage, moisture in the insulation, the condition of seams and terminations, and how the roof is being used. A roof somebody walks on weekly needs a different answer from one nobody touches.
Documentation
Commercial and public work runs on records. We photograph the existing condition, the work in progress and the finished assembly, so there is a file rather than a recollection.
Related work
Commercial covers more than one job, and they are not interchangeable. These are the others in the same family, each on its own page.
Questions we get asked
Not the question you had? Call the shop and ask a person. We would rather talk it through than have you guess from a website.
(801) 382-8898Which membrane is right for my building?
It depends on the traffic, the exposure and what comes out of the exhaust. TPO and PVC are welded and light, EPDM is proven and has fewer seams in wide sheets, mod-bit and built-up are heavier assemblies. We specify for the building rather than for what is on the truck.
Can you work around our business hours?
Usually. Most commercial work can be staged so the noisy part happens when the building is quiet, and we talk about that before the schedule is set.
How long does a commercial membrane last?
It depends far more on drainage and detailing than on the sheet itself. A membrane with standing water on it and a membrane that drains properly will not last the same length of time.
How do I know when a roof is getting close?
Granules collecting in the gutters, tabs lifting or curling at the edges, shingles that look bare in patches, and daylight or staining in the attic. Any of those is worth a look.
How long does a roof replacement take?
Most houses in this valley are a one to two day job once the crew is on site. Steeper pitches, multiple layers to strip and complicated roofs with a lot of valleys take longer, and we tell you which yours is before we start.
What happens if you find bad decking?
We show you. The decking is only visible during a tear-off, so that is when soft sheathing gets found and replaced. We photograph it rather than just add it to a list.
Ask about built-up roofing
Call (801) 382-8898 or send a note. We will look at the roof and tell you straight what it needs.