Rubber Roof on 350sqft $2600 reasonable?

14 years ago

Roof was torn down and replaced in the 70's. I think it may have one or two roll out asphault roofs already on it. The roofer thinks that rubber is the way to go since it has little pitch to it.

He will replace flashing and install new vents too.

What questions should I ask him? How many layers of roofing material are acceptable? If there is only one layer of roofing material on there is it ok for him to install the rubber roof over it?

What typically is the cost per sqft to replace wood if there it rot?

This should be a very easy job. The house is a rowhome in Baltimore approx 11' by 30'. Water rolls from the left to right if you're facing the front door. Only one roofline.

Comments (3)

  • sdello
    14 years ago

    You need to realize that you can't directly compare installed per sq.ft. costs for 350 square feet to 1000 sq ft or more. Sure material costs and installation effort are proportional but there are minimum set up, procurement, disposal, etc. costs that start ata fixed number. Unless the underside of the roof deck is visible, you won't be able to assess its condition without tearing off the old.

    A single-ply membrane either rubber or plastic would be my choice over roll or built-up.

    good luck

  • brickeyee
    14 years ago

    If the roof is EPDM membrane, it wil be a single layer.
    The ony issue with EPDM for retrofit is that it is damaged by contact with asphalt.
    If there is an existing asphalt roof it needs to be removed down to bare wood, and even then a layer of fresh wood is better than taking a chace on damage from asphalt on the deck.
    If the proposed roof is bitumin (AKA 'torch down') it is not really rubber and can be applied over any flat smooth surface. Either bare wood (even if it had asphlat) or a fresh layer for integrity.
    Neither of these materials are very good at spanning any kind of gaps, so surface preparation is iportant. They can cover the normal small expansion gaps of plywood decking.
    EPDM is the better of the two, with lifetimes in excess of 30 years.

  • MongoCT
    14 years ago

    I'd opt for EPDM, and as brickeye wrote, tear off the existing.

    Add a new layer of half-inch or 3/8ths-inch ply (if going over old existing sheathing) or 3/4" ply if going over the framing, and put the EPDM down over the new ply.