ToolsRCool
Well-known member
Hi all. Avid reader, first time posting.
I'm considering to do a tear-down and full rebuild of my detached garage, and would value feedback on the design. Existing is a 26' wide x 24' deep x 16' peak (stick built rafters) permit built unit my dad did back in 1982. Garage has 8' sidewall height, and lower rafter chords are at wall height. Has a decent size pull-down stair storage area. T1-11 wood siding which has aged well but is finally in need of replacement. Sits on a thick concrete slab, because the yard slopes down as it goes back, 42" deep perimeter, continuous pour. City said since I'm reusing the existing slab and same footprint on the rebuild, a survey would not be needed. They are decently reasonable here. They were when I did my rooftop solar panels atop my existing detached garage as well. I highly recommend that to anybody that has a clear South facing roof surface. Our electric bills are $9 a month no matter how much we run the A/C. Very simple to do. 3 parts, 2 wires. Will do a separate post on that in Electrical for anybody interested. 2.5 year ROI.
Local ordinances have changed a bit, now favoring a taller structure. Side walls are now allowed to be 10', and the roof peak is still 16' but now measured at the mid-point, or average from eave to peak. I've confirmed with my local city building authority that this combined with 10' side walls could produce a new peak height of up to 22' (10' wall plus 12' roof, meaning 6' mid), which they confirmed to be correct.
Given above, I'm now considering to turn a 2 car garage into a 4, by adding two 4 post hoists. In addition, push the peak up another 6', and add dormers on each side, to have a decent size 2nd level storage. Dormers are allowed to be up to a max of 50% of the roof length in order to not affect the roof mid-point measurement, as determined by roof slope. I'd love to request a variance for full length dormers, but don't want to the structure to be overly-obnoxiously large to my close neighbors (regular neighborhood), as it will already be growing in size.
If I want to have a 13' main floor ceiling height, and 7' (or so) second story height, I have come up with a way to do so, but have not seen such often, so that is the part I want to publish for opinion. I believe I can achieve a raised 2nd floor height by either using a raised lower chord truss (allowed up to 1/3 of the total truss height), or by using a series of 3 beams, a ridge beam, and then 2 floor beams, supported on each gable end. One end of the two floor beams would rest perpendicular on the garage door header, which seems to be allowed. Other gable end would be 3 posts to the pavement, integrated in the gable end wall build. Dormers are tucked in as to not be considered side wall height.
I've attached a sketch of the idea I am working with a designer on. I don't want to mention him yet (he was referenced here as a recommendation), because this sketch was just sent as a concept of understanding only. It is full of mistakes and things that don't make sense, like the floor beams protruding above the primary roof, and also the floor joists resting atop of the floor beams, of which I would likely want them flush connected with hangars rather than atop. The width is also incorrect, as mine would be 26' wide, not 24'. Really just putting this sketch and post itself out for ideas, both good and bad, or other ideas to incorporate or how to achieve. On a 26' width, this would give me about a 20' width of 13' ceiling for two side-by-side 4 post hoists. Also heavily considering an overhead I beam bridge crane, blame OldCarGuy on here for that and his posts of such, always wanted one. That would be at the 9'-10' area along the side walls, with the cross-beam tucked away against the back wall until needed.
This would be a self-build. 2x6 walls to stuff with insulation, high efficiency furnace, etc.... I have done several construction projects before, just don't have much knowledge on dormers, but they don't seem terribly difficult. Beams, headers, and floor joists would likely sized by the lumber yard. I have ran some prelim numbers using online calculators of such for initial size and pricing.
Apology for length, I do talk too much, but wanted to give some clarity on intent. I'll hand the mic over to the crowd for some opinions, thanks in advance. Responses and future posts will be more brief, I promise.
View attachment 2247603
I'm considering to do a tear-down and full rebuild of my detached garage, and would value feedback on the design. Existing is a 26' wide x 24' deep x 16' peak (stick built rafters) permit built unit my dad did back in 1982. Garage has 8' sidewall height, and lower rafter chords are at wall height. Has a decent size pull-down stair storage area. T1-11 wood siding which has aged well but is finally in need of replacement. Sits on a thick concrete slab, because the yard slopes down as it goes back, 42" deep perimeter, continuous pour. City said since I'm reusing the existing slab and same footprint on the rebuild, a survey would not be needed. They are decently reasonable here. They were when I did my rooftop solar panels atop my existing detached garage as well. I highly recommend that to anybody that has a clear South facing roof surface. Our electric bills are $9 a month no matter how much we run the A/C. Very simple to do. 3 parts, 2 wires. Will do a separate post on that in Electrical for anybody interested. 2.5 year ROI.
Local ordinances have changed a bit, now favoring a taller structure. Side walls are now allowed to be 10', and the roof peak is still 16' but now measured at the mid-point, or average from eave to peak. I've confirmed with my local city building authority that this combined with 10' side walls could produce a new peak height of up to 22' (10' wall plus 12' roof, meaning 6' mid), which they confirmed to be correct.
Given above, I'm now considering to turn a 2 car garage into a 4, by adding two 4 post hoists. In addition, push the peak up another 6', and add dormers on each side, to have a decent size 2nd level storage. Dormers are allowed to be up to a max of 50% of the roof length in order to not affect the roof mid-point measurement, as determined by roof slope. I'd love to request a variance for full length dormers, but don't want to the structure to be overly-obnoxiously large to my close neighbors (regular neighborhood), as it will already be growing in size.
If I want to have a 13' main floor ceiling height, and 7' (or so) second story height, I have come up with a way to do so, but have not seen such often, so that is the part I want to publish for opinion. I believe I can achieve a raised 2nd floor height by either using a raised lower chord truss (allowed up to 1/3 of the total truss height), or by using a series of 3 beams, a ridge beam, and then 2 floor beams, supported on each gable end. One end of the two floor beams would rest perpendicular on the garage door header, which seems to be allowed. Other gable end would be 3 posts to the pavement, integrated in the gable end wall build. Dormers are tucked in as to not be considered side wall height.
I've attached a sketch of the idea I am working with a designer on. I don't want to mention him yet (he was referenced here as a recommendation), because this sketch was just sent as a concept of understanding only. It is full of mistakes and things that don't make sense, like the floor beams protruding above the primary roof, and also the floor joists resting atop of the floor beams, of which I would likely want them flush connected with hangars rather than atop. The width is also incorrect, as mine would be 26' wide, not 24'. Really just putting this sketch and post itself out for ideas, both good and bad, or other ideas to incorporate or how to achieve. On a 26' width, this would give me about a 20' width of 13' ceiling for two side-by-side 4 post hoists. Also heavily considering an overhead I beam bridge crane, blame OldCarGuy on here for that and his posts of such, always wanted one. That would be at the 9'-10' area along the side walls, with the cross-beam tucked away against the back wall until needed.
This would be a self-build. 2x6 walls to stuff with insulation, high efficiency furnace, etc.... I have done several construction projects before, just don't have much knowledge on dormers, but they don't seem terribly difficult. Beams, headers, and floor joists would likely sized by the lumber yard. I have ran some prelim numbers using online calculators of such for initial size and pricing.
Apology for length, I do talk too much, but wanted to give some clarity on intent. I'll hand the mic over to the crowd for some opinions, thanks in advance. Responses and future posts will be more brief, I promise.
View attachment 2247603
