Base ply
The first ply of polymer-modified asphalt laid with laps offset from the cap.
Flat Roofing
Modified Bitumen Roofing Dover, NJ
Modified bitumen roofing in Dover is a multi-ply asphalt roof, usually a base sheet and a granulated cap sheet, used on flat and low-slope roofs, and match the method to the building and its fire risk. Dial (862) 430-1002 to talk through modified bitumen with a local roofer.
Modified bitumen, often shortened to mod bit, is the modern descendant of the old tar and gravel roof, with polymers added so the asphalt stays flexible. Sheets come in SBS, a rubber-modified type that handles cold well, and APP, a plastic-modified type made for torching. Multiple plies make a tough roof that tolerates foot traffic better than many single-ply sheets.
How the sheets are applied matters as much as which sheets are used. Torch-applied sheets fuse tightly at the laps, though the open flame demands care around wood framing, insulation and roof edges. For homes and buildings where open flame is a concern, self-adhered or cold-process sheets are the usual answer.
A few details help the roofer plan. Watch for raised blisters, alligator cracking, bare patches and open laps, especially near walls and drains. Say whether the roof has been coated or patched before, because old coatings and mastic affect repairs.
If the problem goes deeper than it first looked, a Dover roofer may also recommend flat roof replacement or flat roof repair.
Looking for Dover modified bitumen roofing? Call (862) 430-1002 and describe the problem to a roofer who works in Dover.
Call nowThe process
What a mod bit roof job involves
Each layer of a mod bit roof has its own job.
Survey the existing roof
Before planning, the roofer cuts a small sample to see what is underneath and checks for soft decking. That decides between a tear-off and laying new plies over a sound, dry existing roof.
Tear off old roofing
On a tear-off, everything comes down to the deck and damaged plywood or planks are replaced. Rigid insulation and tapered crickets go down next to improve drainage.
Put down the first layer
The first ply is nailed or mechanically fastened on wood, or set in adhesive over insulation. Its laps are staggered from the cap sheet laps to avoid weak lines.
Lay the top ply
The granulated cap sheet is torched, set in cold adhesive or self-adhered over the base. On torched laps, a steady bleed-out of asphalt at the edge shows a good seal.
Flash the details
Walls, curbs and penetrations get reinforced flashing plies that run up and are capped with metal. New drip edge or gravel stop and properly set drain flashings finish the edges.
Walk the finished roof
Once the roof is done, the crew checks every lap, cleans up and keeps a fire watch if torches were used. The last step is a full walk to confirm laps and flashings are sealed.
What is included
What goes into a mod bit roof
Edge metal
New edge metal and drain flashings set into the membrane plies.
Cap sheet
The finished top layer with protective granules with fully sealed laps.
Tapered insulation
Insulation and cover board so water reaches the drains.
Base flashing
Flashing that runs up the wall and under metal where most flat roof leaks start.
Related service
Torch Down Roof Repair Dover, NJ
Torch down roof repair fixes the leaks that develop in torch-applied modified bitumen: open laps, blisters, splits and failed wall flashing. A blister is cut in an X or cut out, the area is dried and sealed, and a new piece of cap sheet goes over it. Granules are pressed into any exposed asphalt so the patch is protected from sun.
In Dover, many torch-down repairs sit close to wood framing, so fire safety is part of every job. Near combustible materials, a cold-process or peel-and-stick patch can replace torching. After torching, a watch period for smoldering material is standard practice.
Related service
Built Up Roofing Dover, NJ
Built up roofing, often called tar and gravel, is the older cousin of modified bitumen: alternating layers of roofing felt and hot asphalt or coal tar, topped with gravel. When the gravel thins out, the asphalt below dries, cracks and blisters. With age, these roofs blister, crack at the flashings and open at the edges.
Most built up roof repairs in Dover start by clearing the gravel, then patching with new plies and setting gravel back in place. When a built up roof reaches the end of its life, its weight and the gravel usually mean a tear-off before the new roof goes on. Many are replaced with modified bitumen, TPO or another single-ply system.
Local help
Modified Bitumen Roofing Near Me
Around Dover, mod bit replaced a lot of old tar and gravel roofs years ago, and many of those are now due for work. From Dover out to Wharton, Rockaway, Mount Arlington and Morris Plains, roofs range from aging two-ply systems with worn granules to newer self-adhered roofs on additions, so the right method depends on what is up there now.
For modified bitumen roofing in Dover, NJ or nearby towns like Wharton, Rockaway, Mount Arlington and Morris Plains, call (862) 430-1002 to reach a roofer who covers your street.
How the weather here affects roofs around Dover
Cold winters bring snow, ice and a long stretch of freezing nights. Heat escaping from the attic melts snow on the upper roof, and the water refreezes at the colder eaves, building ice dams that push water up under the shingles. Coastal storms and heavy spring rain drive water sideways into flashing, valleys and old chimneys. Most homeowners in Dover, NJ have the roof checked in the fall and again after the snow melts.
Why call
Why not wait
Drier ceilings
Small roof problems caught early usually stay small repairs.
Roofers who know Dover
Local roofers see the same roofs and storm damage across Dover and nearby towns.
Know what happens next
Ask the roofer about the cause, the options and the estimate before work starts.
Common questions about modified bitumen roofing
Can a mod bit roof be coated?
A coating can extend a modified bitumen roof that is aging but still dry and sound. The roof is cleaned, repaired and often primed so asphalt oils do not stain the coating. A white coating also lowers roof surface temperatures in summer.
Are torch-applied roofs a fire risk?
Torching uses an open flame, so it carries a real fire risk that has to be managed. Good crews fasten the base sheet on wood decks, keep the flame away from edges and gaps and stay on fire watch afterward. Self-adhered sheets give the same kind of roof without a torch.
What is the difference between modified bitumen and built up roofing?
Both use asphalt, but the plies and surfacing differ. Mod bit replaces the many felts of a built up roof with a few thick polymer sheets, and it skips the gravel. Mod bit is lighter and more flexible, which is why it has replaced built up roofing on many buildings.
Can modified bitumen be installed over an existing roof?
The existing roof decides that. If there is a single, dry, sound roof, a recovery board and new mod bit may go over it. Two existing roofs, wet insulation or widespread blistering call for a full tear-off.
How long does a modified bitumen roof last?
Expect roughly 15 to 25 years from a well-installed modified bitumen roof. Drainage and the condition of the cap sheet granules make the biggest difference. A reflective coating applied before the cap sheet wears out can extend its life.
More questions? Call (862) 430-1002
Often needed together
Flat Roof Replacement
Tearing off or recovering a worn flat roof and installing a new membrane, insulation and edge metal, with tapered insulation where water used to sit.
Learn moreFlat Roof Repair
Fixing open seams, blisters, splits, ponding and failed flashing on flat and low slope roofs, so the roof sheds water again without a full replacement.
Learn moreTPO Roofing
Heat-welded TPO membrane for flat and low-slope roofs, sized to the deck, the drains and the way the roof is used.
Learn moreCommercial Roof Replacement
Full replacement of membrane, built-up and metal roofs on commercial buildings, with nightly tie-ins to keep the building dry.
Learn more
Looking for something else?
See all roofing servicesTalk to a Dover roofer about modified bitumen roofing
Call (862) 430-1002 for a local roofer in Dover and nearby towns.