I have a dilemma regarding whether to add a second floor over an existing converted garage and add a small shop adjacent to it OR Forget having a garage altogether and just build a small shop adjacent to the current converted garage. The dilemma comes from the cost associated with the first alternative and having no place to store tools and or yard machines, ladders etc, etc..
My rational is to build a second story over the converted garage for space for my studio and un-convert the now converted garage back to being a garage. The old garage was side access parallel to the street and that driveway is the only place I can shoehorn in a 15' wide by 25' long shop (where a carport now exists). Doing that necessitates making the garage entrance perpendicular to the street. The dimension will work for the garage as it's 25' deep if approached perpendicular from the street. Tight but do-able.
Even though I have built houses, additions, and single story garages in the past, I have never had the experience of taking off an existing roof and building a second story and re-roofing it. This approach is OK with the building department and I'm allowed to put the adjacent shop in as well.
My questions are:
1) Am I correct in thinking that total project cost will be lower if the existing converted garage roof is demolished rather than trying to save it to reuse? If so :
a)How long should demo of existing roof take in man hours? It's a 25'x 26' gable wood frame. I would sub the demo, framing, sheathing and roofing to a local crew.
b)I know from personal experience that framing goes up fast so I would expect the second story joist reinforcement (if needed) & sub floor laid in 1 day, walls framed in 1 or 2 days, sheathing 1 day & house wrap no more than a day since we would be following the foot print of the first story. 10 exterior windows all the same dimension. 1 36" interior access door from an internal stair well. All this assumes an experienced 4 or 5 man crew, all materials on site & ready to go, Sky Track high lift both man & material capable on site.
c)What I don't know is: how much additional time it would add to the project if I wanted to put a cathedral ceiling hip roof with 24" over hang on instead of another gable roof? Any man hour guesstimates on that? I would want 16"oc to be able to add barrel tile to the roof.
d)Current gable roof on the rest of the house is 4 in 12 slope, should this slope be used for the hip roof or should it have a higher slope like 6 in 12? (We don't get any snow here). Would a different slope look out of place?
e)Another thing I don't know is whether or not any reinforcing will have to be added to the ground floor walls in the converted garage. Any thoughts on that? We'll certainly have to open the old garage entrance to see if it was properly framed in and able to carry the second floor weight.
Thanks for any light you can shine on my questions. :)