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Hi, im about to repalce my flat roof, i live in a row house in district of columbia. I have had several proposal for flat roofs, epdm roof, tpo roof, torch down bit roof which is the best roof,the proposal where for full tear off and replacement, prices $6,500- 10,000. Edpm, 10,000-12600 tpo, $8400 bitm roof. App 730 sq ft roof
 

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I would go with the epdm. You ever have a problem they are easy to patch with just some primer and 6" peel and stick. TPO/pvc are great if you have the money but I would not get wrapped up in the white membrane energy savings crapolla. They are both heat welded systems and would require a special heat gun to repair. Modified in my opinion can require maintenance and I hate dealing with the black tar mastic. Just do your research on the contractors I think is most important and any of these options can treat you good. Dont go with the cheapest guy unless you know its a good one. Roof leaks suck.
 

· Roofmaster
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Which roof

First of all, I dont know who told you that Modified Bitumen is the best type of roof. The best type of roof is subjective, and is answered by "It Depends"

Since you are in a row home in DC, (I am in MD) you do not want to use either EPDM or TPO. These are true single ply roofs, and are not tough enough for the environment they would be in, so a multiply Built up roof, or a two ply SBS hot mopped modified bitumen roof would serve you best. I would not use a torch applied Modified Bitumen roof, as the risk of fire is very great with these.

With either your flashing is very critical, Im thinking you have a short parapet three sides and a gutter rear. Is this correct?

BUR

Tear all of the existing roofs and flashings off down to the deck.(I assume wood)

Inspect the deck for damage, and replace any bad wood. (If your deck is 1 inch full thickness roofing planks, you might need to re cover with plywood.

If you decide on a 3 or four ply BUR with type 4 fiberglass felt (I would) dry nail a G2 (4601 Type 2) Glass base sheet down with cap nails. Nail 6 inches OC in laps and 16 inches OC Staggered down the center one third in from each edge.

Install cant strips at all rising walls.

Mop three or four plies of type 4 felt lapping correctly 34 inches / Number of plies. (Roll width - 2 inches for headlap/ plies 3 ply lap is 11.33, 4 ply is 8.5 inches.

Modified Bitumen is OK, the problem is that any schmuck can buy it, and ruin your roof. You need a kettle for hot with BUR, and most schmucks dont have one.

You can also go cold process. I would go BUR with an aluminum surfacing.
 

· Low Slope Roofing
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In DC? They aren't resistant to bullets
LMFAO, well I don't think a 4 ply with gravel would hold up well to bullets either, I can't say I've ever had the pleasure of doing any research on it but I may make a mock up board for target practice one day.

6" Of Iso, layer of 5/8 Dens deck and a 3/4 in plywood with a 4 ply and gravel may slow the bullet down enough it doesn't enter the home but it will still leak. Also depends on the caliber of bullet and the gun it's shot out of also. That may be enough to stop a 22 but anything less then a 2" steel cover board won't do much for a 50 cal, then again you have to factor in distance too. :laughing:
 

· Roofmaster
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Pitch

9mm Parabellums on the way back down. Ive found them in three roofs so far. 33rd street Baltimore (Mod Bit) , Odenton (FA EPDM) Lit right up on IR. Southeast DC, Smooth Surface BUR.

4 ply BUR with polyester cap sheet, double flood coat and gravel over structodeck coverboard.

I guess pitch would work too. Self Healing. LOL:thumbup:
 

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I never thought about the potential for puncture from bullets dropping back out of flight but I have never pulled one out either.

That is interesting to say the least but certainly not out of the range of possibility in the neighborhoods and areas of DC/Baltimore than you mentioned.

I will have to keep a closer eye from now on.
 

· Roofmaster
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Mod Bit

Mod bit works great as long as you have decent slope, and its installed correctly. I like SBS because it takes less heat to fuse. In DC. Mop one, torch one. If you have multiple roofs tear off, fix deck, red rosin paper, G2 Base, cap nailed thru red rosin, Mop one smooth, Torch one cap Good Roof Properly flashed your good for 30 years.
 

· Roofmaster
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Tear off

If you already have 2 you have to tear off by code, but the reason you dont want 3 is

1. Weight: You are going to overload your structure and leave very little for snow load, (Live Load) This could cause delection, ponding, and more deflection. Its cumulative. You could also start to see cracks in your interior finish and problems opening and closing doors.

2. After all these years you want to get a look at the structural deck, and fix it where needed.

If you hire a roofer that will gladly put a third roof on your home, you are asking for trouble, They dont know Jack.

Good Luck, Buddy and Merry Christmas
 

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If you already have 2 you have to tear off by code, but the reason you dont want 3 is

1. Weight: You are going to overload your structure and leave very little for snow load, (Live Load) This could cause delection, ponding, and more deflection. Its cumulative. You could also start to see cracks in your interior finish and problems opening and closing doors.

2. After all these years you want to get a look at the structural deck, and fix it where needed.

If you hire a roofer that will gladly put a third roof on your home, you are asking for trouble, They dont know Jack.

Good Luck, Buddy and Merry Christmas
Did you hear that the low slope roof / swimming pool is all the rage now...?

:eek:

 

· Roofmaster
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3,732 Posts
Pond

That HVAC condenser teetering on the Parapet to the right is a classic. Wait till you see the ponds after they re-cover........again
 

· Roofmaster
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Tar

Do you mean Asphalt Kits? The cardboard drums that asphalt comes in?

What Type are you looking for Type 1, 2, 3, or 4? Most roofing supplies carry type 3 (Steep) ASTM D312 Type 3

If you do not understand type, you are in over your head. This stuff is heated to about 450 degrees F to mop, it is nothing for anyone who is not a professional roofer to fool around with. It will burn the livin hell out of you.
 
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