Help with flat roof for garage

Hi I’m in a northern cold climate. I Wanna repair and eventually replace my garage flat roof which is approx 14x22
House was built 1958.

1.How can I tell if I have bur or modified bitumen. (It does have gravel on top)

  1. I wanna repair the roof. Should I use fibred or non fibres roof sealer :the cheapest option in assume doesnt last as long ? Or a rubberized or elastomeric coating; which is more expensive ?

  2. (A)If I replace in the future what roofing system should I go with: modified bitumen , peel and stick, epdm or ??
    (B)Which of these have gravel on top ?

If it has pea gravel on it you probably have a Built Up Roof.

You don’t want to use any coatings on this you need to locate the leak, spud away the gravel & repair it with mastic & fabric.

You probably have bigger issues than you may be aware of.

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Doea modified bitumen or other roofing style have pea gravel ??
What is mastic??

Gravel (aka ballast) is most common on BUR and EPDM (rubber) roofs. Mastic is asphalt cement (tar) in a bucket.

So how can I tell if I have bur or epdm ??
Should I use fibered or non fibered roof tar ??
Why cant I just put a coat on the tire roof to get some time out of it ??

If it has pea sized gravel on it you have a BUR if it has 2" or so smooth rocks on it it is probably EPDM.

It’s not likely that you can repair this yourself.

Ok I ll look for a hole and patch it . What type of fabric is it really needed??

So for the future when I replaced the roof . For cold climate what roofing system should I go with

Cotton & fiberglass, I prefer the cotton.

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You have a gravel built up roof (BUR), it is made from multiple layers of felt mopped in hot asphalt or pitch and flood coated with asphalt and gravel embedded. You need a spud bar for large areas or shingle bar for small areas to break loose the gravel and flood coat to get to the felts to repair. Small holes are not likely on this system due to how tough it is. Old BURs crack when they get old. If you can find the crack or any openings you need to spud around it and use Plastic Roof Cement, lay in fiberglass or cotton mesh 6" wide, and coat the mesh with Roof Cement.

If you want to coat the roof you need to use asphalt resaturant, however if the felts are rotting or cracking this will not stop future leaks.

You can replace with anything you want, you will need to either tear off the BUR if wet underneath, or go over the BUR. If going over you will need a layer of insulation or cover board before the roof membrane can be installed.

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The gravel is loose why would I need to break it apart for the repair .
Is plastic roof cement same as rubberized??

The gravel is embedded in the asphalt. The rock is applied at 500 lbs per 100 square feet and roughly 280 lbs per 100 square feet get embedded in the asphalt.

There are multiple kinds of roof cement, rubberized roof cement would also work but is more expensive.

Honestly, you should just pay to have this fixed. This type of roof can be repaired but if you don’t know what you are doing you will just make it worse. Find a company that does commercial and residential, a lot of residential roofers have no idea how to fix this kind of roof.

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No one in my area knows what they are doing with flat roof. All different opinions. Even to fix the way the roof drains is currently in correct . And no one even notices till I mention it . At the sides ots draining into the flashing and going into the garage . Just the rear where it slopes down has the proper edging…

So u are saying to scrape it a bit so that there is better adhesion and i get rid of the cracked part

We can help you greatly
If you give us some pics.
Get on the roof, sun behind your back.

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Ok I ll take some pics. Why with the sun at ?my back ??

So that the pictures don’t get washed out by the sun

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I’m curious what If I cover the bur with something like this or similar

https://www.homedepot.ca/product/gaf-liberty-3-ft-x-34-ft-100-sq-ft-sbs-self-adhering-cap-sheet-in-black-for-low-slope-roofs/1000731241

Where does it say that this product can be laid over a BUR?

And what about the pea gravel?