Built-up roofing, often called BUR or tar and gravel, is made of several layers of roofing felt mopped together with hot asphalt or coal tar and finished with gravel or a cap sheet. It is heavy, tough and forgiving of foot traffic, and plenty of older Ventura buildings still have one. When a BUR roof leaks, the cause is usually blistering, cracked flashing or plies that have dried out. We compare a BUR repair or reroof with modified bitumen roofing, which uses similar asphalt chemistry in fewer, thicker sheets.
Your estimate will say how many plies are on the roof, what the surfacing is and how much of it we plan to keep.
We take a core cut to count the plies and check the surfacing before deciding on removal or calling a surface repair finished. Downtown Ventura has many older commercial buildings, and the Ventura Avenue corridor has industrial and light-commercial properties, so we see a wide range of BUR roofs, some with two or three roofs stacked on top of each other. Each one gets checked on its own. The building's access rules and work hours are worked out with the owner or manager before we start.
What is already on the roof
A BUR roof can hide a lot. There may be an older roof underneath, wet felts between layers or patches made with materials that do not bond to asphalt. We look at any drawings or past invoices you have, then inspect the roof and take cores to see the layers for ourselves. Any part of the roof we cannot get to is flagged on the estimate.
Mystery patches get a small test before we decide whether new asphalt can go over them.
Our commercial roof inspection covers the gravel surface, the flashings and the edges. The cores tell us whether the layers underneath can stay. If the deck looks damaged or overloaded by stacked roofs, an engineer may need to review it before we plan a recover. Building codes also limit how many roofs can be layered, which can force a tear-off.
Wet insulation and tear-off
Water that gets into a BUR roof spreads sideways between the plies and into the insulation. An evening infrared scan, backed up by cores, maps the wet sections before anything is torn off. Wet felts and insulation come out, and the insulation and cover board is replaced so the new roof has a firm, dry base. Dry areas that are well bonded can often stay.
When an opening reveals more wet felt than the scan suggested, the crew pauses and we walk the owner through it.
Tear-off on a BUR roof is heavy, dusty work, and gravel removal adds weight and mess. We plan where debris goes and how it comes down before we start. If the deck is rusted or rotted under the wet area, we show it to the owner and price the deck repair separately. That way the estimate reflects what is really under the gravel, not just the square footage.
Where BUR meets other roofs
Many older buildings have a BUR roof next to a newer single-ply section, a metal roof or an addition. Those tie-ins are frequent leak points. If part of the roof is being replaced with TPO roofing, the joint between asphalt and TPO needs a compatible transition detail, since TPO and asphalt do not bond directly. We build that joint at a curb, a raised edge or with a manufacturer-approved transition.
Walls, curbs and parapets get new base flashing that matches the new roof.
Changing roof height can affect drains, scuppers and door thresholds, so we check those before deciding on the new assembly. If a rooftop unit or drain needs to be adjusted, the right trade handles it and we schedule the roofing around that work. The goal is a roof where every edge and joint has a clear, sealed finish, with no loose laps left at the transitions.
Related Roofing Work
Coordinating with other trades
BUR work often uncovers items outside roofing: a drain that needs a plumber, an HVAC unit that has to be lifted, or wiring on the roof that needs an electrician. We list those separately so the owner knows who is responsible and when. Our roof condition reports color-code the roof by zone so everyone can see what is ready to start.
A zone gets torn off only when the plumber or HVAC tech is done there.
Hot asphalt work also needs planning around the building. Kettles, fumes and fire watch rules are worked out with the owner ahead of time, and we keep the kettle away from air intakes and doors. Where hot work is not a good fit, cold-applied or torch-free options can be considered. Deliveries and debris removal are scheduled so they do not block tenants or customers.
Closeout and future repairs
Your closeout packet includes pictures of the new plies and flashing, the spots where insulation or deck was swapped out and a list of materials. Each sealed edge and tie-in is noted with its location. Anything another trade still owes, and anything we never got eyes on, gets its own line.
For older buildings around Downtown Ventura, we also note the roof layers we found.
Later, a commercial roof repair crew will know from this packet which plies are new and which older layers were kept. Changes made mid-job are pinned to a spot on the roof plan, so nobody has to guess where the extra work went. That helps the next roofer find the right starting point instead of guessing what is under the gravel, and it gives the owner a clear picture of what was replaced and what is original.
Common Questions
How do you decide which parts of a built-up roof can stay?
We take core cuts to count the plies and look for wet felts and insulation, and we use an infrared scan to find wet areas. Dry, well-bonded layers can often stay. Wet or blistered areas come out, and the estimate says which is.
How does built-up roofing compare with other options?
We compare BUR with modified bitumen, TPO and other systems using the same inspection results. Each option includes the same repairs, wet insulation removal and flashing work, so the price difference reflects the roof itself, not missing items.
What has to be worked out before a new roof meets the existing BUR?
The transition detail. Asphalt and single-ply membranes do not bond directly, so we plan a compatible joint at a curb or edge. We also check drain, curb and threshold heights before installing a different roof next to the old one.
What will the closeout list for work that is not finished?
You get a short punch list: uninspected spots, other trades' open items and any scope changes, each with a location. Each item has a location so the owner knows exactly what remains.
Get your built-up roof inspected
Tell us where the building is and which roof section worries you, and pass along old invoices if you have them. After a walk and a few cores, you get a price that separates the layers we keep from the ones that come off.