Dormer Vs. New Roof

Baghuan

Hello all. I recently purchased a 1950's brick house, which I guess I would describe as a Cape Cod. It is one storey with a full attic, roughly 35' by 35'. I would like to convert the attic to living space. Currently the peak is around 10' from floor, and there is roughly 16' of width that would be usable (before you run into head clearance issues). According to the home inspector, the roof is about eight years old.

My questions are:

1) What is the best way to increase the usable space (large shed dormer, vs. new higher roof)? Are there other options?

2) How much (very roughly) might the above options cost to have done professionally.

3) Can I add the shed dormer by supporting the existing roof, cutting out a section on one side, jacking that section up to change the pitch, and then framing new support walls and re-attaching the section? Would I be crazy to attempt that with a bunch of construction employed friends(after getting an architect/engineer to approve)?

Thanks in advance.

Glasshousebltr

35 x 35? 1950's? brick? I'll bet what you have is a 4 square.

I bought one and did a complete remod on it in the early 90's. I turned the attic into the master bed by doing what your asking about.

Got any pics?

Bob

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Bob

Baghuan

No pics with me, but I will take some and post them tonight. What exactly is a four square?

A master bed/bath is just what I would like to turn the attic into. I am okay with tackling the stairs, plumbing, framing, drywalling electrical, etc, but a dormer or somehow raising the roof is a little beyond what I would be comfortable doing at this point without more direction and consultation.

How did you remodel yours (dormer/new roof)? Approx cost (assuming you were paying yourself, as I probably would be)?

Glasshousebltr

Most 4 squares have a hip roof. I took out the back hip and converted it to a gabel. Installed a dormer on the opisite hip with a great mountian view. A window, 2 skylights, and a sunken tub later, I was a kicking back in style.

Also, I should add, a devorce later and she was kicking me in style, and I was sleeping in card board box.

Bob

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Bob

Glasshousebltr

I just noticed, I didn't really explain the 4 square house.

Hip roof. Normally 2 stories, in a square, rooms right, left, front, back almost like blocks on top each other. Balloon frame, most built between the late 20s and early 50s.

A lot of them have a brick porch with a hip roof on the front of them.

Bob

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Bob

Baghuan

Like I said, the construction is brick (maybe over cinderblock, I don't know). The ceiling of the first floor/floor of the attic is 2x6's for one third the width, and then 4x6's for the other two thirds, overlapping on my load bearing wall. The roof is gabled, all 2x6 rafters, meeting at the ridge with a triangular gusset. There are no horizontal pieces to complete the triangle of the truss in the attic itself, as, I imagine, that is what the floor of the attic is doing. At about three feet high, there is a knee wall (or what will become a knee wall).

Is it possible to cut a large shed dormer into one side and slavage the existing roofing material by just changing the angle of that section of roof and then building my new walls? Or would it make more economical sense to have the whole roof replaced and raised up about five feet? The space would be made big enough to be usable by only adding the dormer.

I tried to post pictures, but being new to the site I cannot post URL's as of yet.

ron schenker

For a reasonable fee, most reputable home inspectors will advise you on what options you have and how to go about getting it done. Give him a call and tell him what your plans are.

Baghuan

I will give our home inspector a call.

If you guys have any idea on price, I would love to hear it. I know my situation will be unique and the estimates may be high or low, but if your ballpark is way out of my budget then it may end up being a non-starter.

Thanks for all the help.

Grumpy

We did an 8'x8' dormer shell on an unfinished attic a year or two ago. We did the roof at the same time, and the cost for the dormer was about $8k, which includes siding and a window. The roof was about $20k with skylights. An architect will cost you $2-5k to draw up the plans.

If it's 10' from floor to peak, you might not have enough clearance. My guess is you have Collar Ties at about the 7' mark? Don't remove these! Can you deal with a 7' ceiling? Also don't remove the knee walls.

Also when you finish the attic and add a ceiling and insulation be sure that you have at least 1" of open space on the bottom of the roof deck. In other words don't stuff it up with insulation, leave it loose!

kenvest

what would happen if you moved collar ties up a foot?

reveivl

You have asked if you can lift the existing roof up into a shed and save yourself some time/money. The answer is NO. It doesn't work, it's slow, gives you a lousy finished product, and it's really difficult to do. Just my opinion, Rich.

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From where does knowledge come? If you need to know what is in a box, you could ask someone (not reliable), you could pray, (not useful), you can consult with the scripture (not helpful) or you could open the box (science)

Joe Carola

Baghuan,

If your existing ridge is to low to put a shingled roof on your dormer you can always extend the front rafters by adding smaller rafters to the existing ridge extending up to a new ridge. That will give you a steeper dormer roof so that you can put shingles on instead of a roll roof. Just make sure it's designed where your collar ties will be nailed into the existing ridge.

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Joe Carola

Grumpy

You run a strong potential risk of sagging rafters if you move the collar ties. This will damage your roof and ceiling in the attic.

Also if you hang a ceiling from the collar ties your probably going to want to reinforce them. My guess is they are 1"x6" (3/4" actual). Consider a 2x4 on the opposite side for strength!

I'm not an archiitect, engineer or framing carpenter (though we do roof framing repairs), but that just makes sence to me as a roofer who has seen lots of damaged roofs due to failing framing.

Baghuan

I spoke with a local contractor that does some DIY consulting work, and he echoed the things you guys are saying. He said it would be best to demo the section of roof where the dormer is going, double up the end rafters, and build a new dormer. He is going to provide the onsite knowledge for a reasonable fee, and I am going to provide whatever labor and materials he tells me I need. I am having an engineer from work draw up the plans, and we will see if the town approves them. If not, then I will find someone who will come take a look and sign off on the plans.

Grumpy, were those costs material costs or total including professional labor? I do have collar ties at about 7'. I would like 8' ceilings. Can I move the ties as Kenvest suggested? Perhaps replace them with a triangular metal plate that is higher? As for insulation, I think I would like to add more up there. The rafters are 2x6's, and right now have a singe layer of fiberglass. Can I scab on some wood to make the space deeper prior to finishing? Is there a product that exists that goes between the rafters that can help maintin my air gap? The knee walls are staying put, all the modifications will be done to leave them, but even right now the top plate of the knee wall does not touch the rafters. It is about 3/4" away. Why is that?

Again, thanks for the thoughts and advice.