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My wife and I are completely remodeling our 100+ year-old home in extreme Northern Michigan (on the Keweenaw Peninsula). The home is a basic two story with a walk-up attic. I’m going to replace the roof (the entire roof structure – Rafters and all), and I’m wondering if, after I remove the old roof, I can add about 18 inches to the side walls to provide more room in the attic. Are there any significant structural things I should consider?
One unrelated comment: The floor trusses on the second floor are 40-foot 2X10s running the length of the house. It seems odd. Is this common?
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Hi there,
Assuming that there isn't an existing knee wall around the perimeter, you shouldn't have any problem with installing an 18" wall. Make sure that you have proper blocking under the bottom plate of your new wall. Pay special attention to the sides where the floor joists butt into. Structurally, your roof load will be the same.
If you have an existing wall and you are going to add to it, you have to make sure that your baseplate is firmly attached to the top plate of your existing wall so that it doesn't feel like it could rock or tilt. I would prefer to remove any wall down to the second floor level and build fresh.
Gabe
(a 40 ft long piece of 2x10 would be uncommon but the running of the roof members on the lenght would not be.)
*Rebuilding the entire second floor from scratch would be more than you most likely care to do. Also, adding an 18 inch wall atop of the the top plate of the existing wall (assuming it has one) would not be very structurally sound. The best solution here would seem to be removing the existing top plate and then adding new studs along side the existing so that they would extend 18" above and at least 2' below the top of the previous wall height. This would help to maintain your sheer strength of these walls. you can then block in the wall with short filler studs above the old studs to also maintain your stud "centers" If you only added a new 18" wall atop of the existing plate, your new wall would be very susceptible to pivoting over from the forces of nature and the outward force of your rafters.I hope this all makes enough sense to you. It's always easier to show you than tell you.Pete Draganic
*JEdwin-If you add a knee wall then you are creating a pivot point where it ties into the top plates of the wall below. (like Pete said). You will need to counter the outward thrust of the rafters against the top of the knee wall. There are many ways to accomplish this discussed in one form or another in the archives here. Might be a good idea to get an engineer's input- maybe a professional framer to do the raftering. The roof is kinda an important piece of the whole house as far as keeping it standing...
*...i like extending the walls thru the plate (ala Pete0sounds like your new structure will be stronger than the the existing... what were the ceiling joists ... they were tied ACROSS the house right...?interesting to get inside the mind of the one who decided to cut, buy, or install 40 foot floor joists running the length of the house...any other unusual quirks in this one? are you sure there isn't a joint and you just can't see it?sometimes boat builders did unusual things when they built houses...since you are looking for more room in the ATTIC.. this means the ceiling joists / attic floor joists will stay where they were.. so they have to sit on something...sounds like you could use some professional structural advice....do it on paper..not with wood... get your design right before you get started..
*Just a shot in the dark, but would some sort of custom trusses do the job? I'm assuming platform framing in the existing structure, and a willingness to give up some floor space near the attic eaves.Ron S?Trying to help, Steve
*I was kind of wondering if this house is balloon framed? Seems we had a thread here a year or so ago that mentioned some old houses with the floor joists running the length of them. You might try a search or maybe somebody else here remembers it.JonC
*J Edwin - (And Steve T.)Never heard of or seen b any lumber 40' long. They'd probably be worth a fortune to lumber reclaimers. I don't doubt that some sort of attic trusses could work well on this job, but they're awfully expensive. Their usefullness in this situation could further be complicated by things like how the stairwell runs. An 18" kneewall could be built into the ends of trusses, but that would only make them more expensive. Assuming that you don't use attic trusses - You're using the ceiling joists as floor joists by doing this - They might not be up to it, depending on the span between bearing points. You also need to look at bearing walls below, to make sure headers and such are capable of carrying the extra load. From your breif description, it sound to me like this is way out of line for a DIY project. I think ya oughta call in some hired guns to look over the situation.Best of luck with it, whatever you do.
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My wife and I are completely remodeling our 100+ year-old home in extreme Northern Michigan (on the Keweenaw Peninsula). The home is a basic two story with a walk-up attic. I'm going to replace the roof (the entire roof structure - Rafters and all), and I'm wondering if, after I remove the old roof, I can add about 18 inches to the side walls to provide more room in the attic. Are there any significant structural things I should consider?
One unrelated comment: The floor trusses on the second floor are 40-foot 2X10s running the length of the house. It seems odd. Is this common?