Any general contracotrs out there? Rough costs to extend a garage by approx 16 x 22' ?

Below is a rather crappy screen shot from Google maps of our house. 

Ignore the crap behind, that's a sail boat, firewood, pavers and yard tools/toys.  You can see the attached garage on the right, that's approx 21x22".  Behind it you can see a small square area between it and the house.  It has a sloping roof that attaches to the East end of the house and blends in to the back side of the garage.  Currently that's the hall/door to the garage with just enough room for a small laundry with the washer and dryer side by side, no room for a sink.  Previously it was a little half bath until we knicked out the internal wall and moved the laundry upstairs from the basement. 

There's a major issue with the roof of the garage.  The main ridge runs in the same direction as the main house roof with a gable facing the street.  Bizarrely the main roof isn't made of 'A' frames, the cross brace is perpendicular to the roof trusses so the ridge has slowly been sagging over the last 67 years.  I'm sure as a result I'm for ever chasing a leak that's been getting worse.  No amount of sealing will fix it icluding repalcing the roof bords, adding a huge copper sheet under there in the joint area and double ice damn under there when we did the roof in 2000.

Normal roof

Our Garage roof.

There are ways I could fix this, but what I've always wanted to do is extend the garage back 16+ feet make that part of the building approx the size of a 2 car by 2 car garage.  Rather than that though, I want the garage to be 'L' shaped and add a full mud room, laundry and half bath in what would be a fourth bay if I just extended the garage.

All I want is a rough cost.  Is this $30k, $40k or $50K to build and finish?  I don't want to start calling contractors yet as we're just in the 'can we afford this', what's the cost of money, what else needs doing, what other family / financial goals do we have?  stage of planning.  I don't want to waste peoples time coming out and getting quotes for something that may not happen, or if id does I doubt we'd be breaking ground until late this year, more likely in the Spring.  This is Michigan don't forget, we have a major winter only five months away.

A bit more detail.  There is a full basement under the whole house, including the odd little laundry room at the back.  The garage is obviously on a slab, and it's about 18" (two steps) down from the floor of the main house.  The AC unit is currently behind the garage and it would also need to be moved.  There is/was a lawn sprinkler system that comes out behind there as well, but it hasn't been used / operational in over a decade as we don't believe in wasting that much water for vanity.  I'm not worried about keeping it, just mentioning things that may get in the way of a 'simple' add on.   I mention the difference in the floor level as I assume even around the front and side of the existing garage we would need to add that 18" to the top of the existing walls?

Exactly how far to go I'm not sure.  The existing internal dimensions are 20'9" wide with a 16" garage door by 21'6" deep.  I figure I probably don't need to go back more than 16' to make the extra bay in the L, and yes if we're borrowing money to do this I'd like to get a hoist back there.

Anyone want to throw out some rough figures for what I want to do, or is it really just too vague and situational dependent.  Googling the answer doesn't work as the estimates they provide are so wide ranging as to be useless and they all want to hook you up with local builders.  I'm not at that stage yet, just the family financial feasibility calculator point.

Thanks

Have zoning/code rules been considered, if pertinent?

In reply to bluej (Forum Supporter) :

I should be able to go back without issue.  The closest issue I have is that the East wall of the garage is technically 6" too close to the lot line.  But it was built like that in 1953.  I'm sure I'd get a variance to carry on back at the same level, worst case I"d have to step the wall inwards 6".  I don't want to add a second story, although several people in the neighborhood have done that, so again I don't see an issue if I want to raise the side walls 18".  Finally the head of the village planning board, and VP of one of the largest architectural firms in SE Michigan, lives opposite me so I will pop over and ask.  But I think I should be okay.  

It's like asking how long a string is, regional prices vary hugely, like double or triple the amount from least to most.

Ask a local contractor for the best idea.

$80-120/sqft is a absolute ballpark.  So ~$35k.  My guess is adding extra depth won't cost that much and less won't save much.  So for an extra $2K you may be able to get a 20*22 instead.

I only say that because I know it will be frustrating when everyone tells you you can't do any estimates without a design and a contractor and consideration of local stuff.     And that's good advice because you may think it's going to be ~35k and of comes in at $50K.  If that happens I'm sorry.  

I'm basing that estimate off of having a 1000sq-Ft detached built for 40K and a 600 sq-ft 2nd floor finished addition (1 bathroom, 1 laundry, new furnace) for 70K with no flatwork.  So the finished addition was  ~$120/sq and the Unfinished garage was $40/sq.  This is in Central Illinois, Low permitting costs, No inspections, all work was licensed and insured in last 5 years.  

Just to be clear, the current garage roof structure would be redone in your preferred scenario and the addition would be tied into the new roof structure?

And the addition would have a poured footer and slab?

What happens to the existing rear wall of the garage?

Would the rest of the house be re-roofed at the same time to match the addition?

Do you have enough overhead in your current electrical to handle the lights/outlets, etc? Particularly a dryer for the laundry area? Or will you need more service and a new panel?

Moving the AC sounds like an expensive pain to me. If some or all of the new space will be heated/cooled, you may need to upsize your HVAC anyway to handle the additional volume which turns "move the AC" into "all new HVAC system".

Will the entire space be insulated and/or finished in anyway, or are you just looking for closed up walls and a roof?

Plumbing for the mudroom/laundry would add cost, especially if it's finished space.

I'm no contractor, but $35k sounds like a steal to me for that amount of work. I'd guess $50k+ easily. Here's my very rough, uneducated guess:

$8-10k concrete/foundation

$3-5k electrical

$10-20k for redoing the existing roof structure and adding new decking/roofing

$5-7k for HVAC

$3-5k for plumbing

$15k for new framing, sheathing, etc. Exterior wall material could really change this cost

$5k for insulation/drywall

In reply to nocones :

Thanks, that's a great starting point.

STM317 said:

Just to be clear, the current garage roof structure would be redone in your preferred scenario and the addition would be tied into the new roof structure?

And the addition would have a poured footer and slab?

What happens to the existing rear wall of the garage?

Would the rest of the house be re-roofed at the same time to match the addition?

Do you have enough overhead in your current electrical to handle the lights/outlets, etc? Particularly a dryer for the laundry area? Or will you need more service and a new panel?

Moving the AC sounds like an expensive pain to me. If some or all of the new space will be heated/cooled, you may need to upsize your HVAC anyway to handle the additional volume which turns "move the AC" into "all new HVAC system".

Will the entire space be insulated and/or finished in anyway, or are you just looking for closed up walls and a roof?

Plumbing for the mudroom/laundry would add cost, especially if it's finished space.

I'm no contractor, but $35k sounds like a steal to me for that amount of work. I'd guess $50k+ easily. Here's my very rough, uneducated guess:

$8-10k concrete/foundation

$3-5k electrical

$10-20k for redoing the existing roof structure and adding new decking/roofing

$5-7k for HVAC

$3-5k for plumbing

$15k for new framing, sheathing, etc. Exterior wall material could really change this cost

$5k for insulation/drywall

Great points.  The existing rear wall would be removed.  This would be a completely new roof, nothing remaining of the original.  Yes it will need a slab pouring and the AC moved.  The rest of the roof will just need a second layer of shingles in a year or so.   We did the roof ourselves in 2000.  Complete tear off, $1,600 in materials just to repair roof boards and soffit etc. as all it had had since being built in 53 was a second layer of shingles.  No underlay, no ice damn nothing.  Just shingles onto 1x6 boards!

I don't think the AC will need upgrading, this unit is 25 years old after the old one got struck by lightning.  Sounds old now I say it!  I think it's probably big enough as I don't plan on providing AC to the garage.  I do have a large ceiling mounted space heater for the winter that can be re-used.  

From what people are saying I've got a gut feeling in the $40-45K range.  

That's good enough for back of the napkin additions, but yes we'll be contacting someone in the next few weeks to get a professional view.

Electrical is fine.  We already have 220 to that area and the main fuse panel in the basement is relativly close to that end of the house.

Pricing might also be dependent on how busy the contractors are in your area.