Between 265 & 485 SQ/FT Seattle shared driveway garage project (Maybe....)

[HassB]

I've been lurking in these forums for the last 1-2 years watching with envy as folks take on a garage build. I am hoping to start my own early next year but I'm still at the very early stages and it might all fall apart, but no harm in getting some idea's out there and feedback.

I live in Seattle, WA (transplant from the UK) and I'm in the blue house on the left in the picture below. We have a shared driveway and and then a shared garage at the back.

This project has lots of fun challenges,

• Small lots
• Shared driveway
• Shared garages that are already very close to the property line
• The need to talk my neighbor into doing something too
• Begging for easements from everyone;

The diagram below gives some context on our lots on this block (I'm 2003)




The current garages are both 10' x 20' with a shared wall down the middle. After you put a box in them it's almost impossible to put a car in. However, it's been great for storage and DIY workspace and will still be if it all falls apart.

I want to make the garage bigger and also build a space above for a home office/guest room/teenager hang out, this would be considered a DADU (according to the planning department)

I can't bring the garage any more forward as it would be impossible for me to pull even a small car in and out, so I think it will continue be ~1' from the property line, we have 5' easements in Seattle for this location in the parcel.

I like all my neighbors and also want to build something that isn't a complete monstrosity and keep as much of the garden as possible





I get on really well with my neighbor to the right and they like the idea but as you can imagine it's mine dream that will then cost them lots of money. So while my designs cover both garages I may end up doing something on my own (or nothing). All good either way.

Every square foot counts and I'm from the UK so having a shared wall is nothing new to me, but we would both need to put a staircase somewhere so I thought why not use that as the party (shared) wall and so we both only need 1.5' each of staircase space

The diagram below shows the original garage overlaid with the new proposed footprint and the new staircase in the middle, the neighbor on the back left has suggested they would be ok with giving the easement (nothing firm yet, but they have said this multiple times), and I I've made an L Shape Design to lessen the impact from the house.




This is how space would be inside just for context, I have a Rav4... and my neighbor a Model Y both to scale.



I might have hit my limit on pictures, so will post a reply with more info

The garage would have 10' high clearance before the joists and the upstairs would have 6' high side walls and a ridge beam ceiling to reduce the impact

Let me know your thoughts/ideas;;;

 

[TX4runner]

Are you planning car stuff with lifts or could the garage be 9 ft and 7 ft walls for the 2nd floor. 6ft on the 2nd floor feels tight even it it peaks in the center. Not a designer or engineer so just some random guys questions. But the expansions looks like it will add a lot of usable space if you get approval

 

[HassB]

@TX4runner I have lots of ideas so wanted to keep it as flexible as possible and I thought based off all the other posts 10ft is still be a little low but viable. It's currently 9' before the joist so adding another foot.

Yeah understood on the kick wall height on the 2nd floor, I'll post some picks with angles (just me using Visio) I'm well under the height limit so I can probably do 7' as you say. But trying to keep it as low as feasible so I get the easements. But ill draw it up and post it. Thanks for the feedback.

 

[HassB]

EDIT: I increased the 1st floor height and lowered the garage height slightly in a post a few down from this one

I mocked up some front and side views with what I think are reasonable assumptions on joist height and wall thickness etc..

I'm only 5.8' but using a 6' scale person and my Rav4 for context.

@TX4runner as you mentioned I can eat ~6-12" from the garage to make the upstairs higher if needed (closers to a 7' kick wall)



Note: side view is only of the thinner side section and so not including the front of the garage

Seattle Rules (LINK) (might be out of date but good enough for now), I can probably use an average for ground height given the difference between the front and back but it looks like this will be ~23' from the lowest point, which works (just) anyway

 

[TX4runner]

The picture visual helps. It doesn't look as bad as my vision of getting to the top of the stairs at the back wall and being very close to the ceiling at 5'11.

Part of the question for me was which goal has higher priority, tall garage projects or hangout time upstairs. I'm coming from a garage with about 8 foot walls before the rafters. I knew I couldn't get a lift in there so I got QuickJacks and lift cars up about 2 ft. I just moved, and the new house has 10ft walls, which would be very tight to get a 4 post to stack cars and wouldn't allow standing upright if lifting a car to work under it. So depending on what your doing, 10 ft may be a limbo zone and just thinking if no full size lift, would the extra foot be more comfortable on the 2nd floor. I'd love to punch up my ceiling one day to give move room for a lift, but that's way down the line at best since we just moved in and there are plenty of other priorities for that amount of money. Just food for thought depending on how you want to use the space.

 

[marinusdees]

I mocked up some front and side views with what I think are reasonable assumptions on joist height and wall thickness etc..

I'm only 5.8' but using a 6' scale person and my Rav4 for context.

@TX4runner as you mentioned I can eat ~6-12" from the garage to make the upstairs higher if needed (closers to a 7' kick wall)



Note: side view is only of the thinner side section and so not including the front of the garage

Seattle Rules (LINK) (might be out of date but good enough for now), I can probably use an average for ground height given the difference between the front and back but it looks like this will be ~23' from the lowest point, which works (just) anyway

Circumstances change, people change, and move (in and out). Sounds like a long term nightmare to me. My suggestion, look for a bigger lot with no encumbrances.

 

[HassB]

you are right @marinusdees however moving isn't really an option as we love it too much where we live so worth the risk, but once everything is built it becomes a minor one, like I said I'm from the UK and so a shared driveway (shared stuff) etc.. is very common. Adding a staircase gives additional separation I don't have today.

If we find (once I get the proper survey done) the current garages are sitting on the lot line then we're probably out of luck and same on the easements but no harm in trying.

So my goal is to make the most of what I have, if it all falls apart (before I spend too much money prepping) it's not the end of the world (just a little sad).

 

[HassB]

@TX4runner I think you're sold me on it.... to be honest I think I only want to put a lift in because of all the cool threads I read , I like to tinker but can make that work with less space (little lifting space)

Making adjustments to support a 7' kick wall, also you're not wrong about the steps, that might be the most help by removing a tread!

 

[HassB]

Happy Thanks giving folks;

Updated the heights to now have a 7' kick wall on the 1st floor (and one less step!) and then a ~9' Garage height

 

[kitdoctor]

That is an interesting property arrangement with the driveway straddling two, what I assume, are distinctly separate parcels of land and then there's a shared building.

Here in Australia a low ceiling height would be anything less than 2.4 m (94.5"). To have ceiling fans, at least 2.7 m (106.3") is required.

With four post hoists the heights of the two vehicles are critical. I have a 70's Falcon sedan and '71 Mustang and with a 3.2 m (126") ceiling height it's very tight, with 100 mm (4") clearance to the ceiling.

My hoist has air activated locks, so you have to factor in firstly raising the lift slightly to get it off the locks before you can start the lowering process.

 

[HaiKarate]

I can't imagine hating money and freedom enough to deal with living in Seattle/KC. Best of luck to you - you will need it.

 

[HassB]

@kitdoctor yeah ideal of a car lift I think is now gone;;; even I marked out the current height in the garden and it's a bit of a monstrosity, so working on how I can get it a little lower still;

 

[HassB]

@HaiKarate not sure what the /KC is but Seattle is where my wife was born and grew-up so it's home. It was also an easier transition for me coming from London versus going to a smaller town. So we're happy here and will take the pro's with the con's

 

[HaiKarate]

@HaiKarate not sure what the /KC is but Seattle is where my wife was born and grew-up so it's home. It was also an easier transition for me coming from London versus going to a smaller town. So we're happy here and will take the pro's with the con's

King County - aka the second circle of hell that envelops Seattle proper.

 

[xtremek]

That's one wild layout and I love it. I hope it works out for you because the design is so unique. All I have are boxes, which are boring. Useful, but boring.