Cost of reversing double garage conversion

ignite_me

Good afternoon,

I'm in the process of buying a fabulous house but its original double garage has been converted into living spaces. And I would like to convert it back to keep our cars inside.

As a ballpark figure, how much it would cost to convert it back to one big garage? Just a rough estimate would be highly appreciated. 

Thank you 🙏

ignite_me

This is the floorplan of the garage:

casper_gutman

You're proposing to buy a house with a converted garage, for which you'll pay a premium, and then spend more money (I'll let others better qualified guess at how much) on reducing the value to that of other, similar houses you could have got for less!

Is this house really special in other ways? Does it meet requirements that very few others do? Is there enough land that you could build an additional garage (either attached or separate) instead?

On the face of it this doesn't sound sensible and I doubt a mortgage lender would be too pleased....

ignite_me

casper_gutman said:

You're proposing to buy a house with a converted garage, for which you'll pay a premium, and then spend more money (I'll let others better qualified guess at how much) on reducing the value to that of other, similar houses you could have got for less!

Is this house really special in other ways? Does it meet requirements that very few others do? Is there enough land that you could build an additional garage (either attached or separate) instead?

On the face of it this doesn't sound sensible and I doubt a mortgage lender would be too pleased....

I got the house for well under the asking price and on par with similar houses without the garage conversion. So yes, I would say that I am not paying a premium for it and it'd be worth it for me to make my house the way I want it.

GDB2222

ignite_me said:

casper_gutman said:

You're proposing to buy a house with a converted garage, for which you'll pay a premium, and then spend more money (I'll let others better qualified guess at how much) on reducing the value to that of other, similar houses you could have got for less!

Is this house really special in other ways? Does it meet requirements that very few others do? Is there enough land that you could build an additional garage (either attached or separate) instead?

On the face of it this doesn't sound sensible and I doubt a mortgage lender would be too pleased....

I got the house for well under the asking price and on par with similar houses without the garage conversion. So yes, I would say that I am not paying a premium for it and it'd be worth it for me to make my house the way I want it.

I’m not a builder, but £20k? 

A lot depends on how the conversion was done. For example, is there a suspended timber floor, and the original garage floor is intact underneath?  Also, what finish do you want?

The plan shows internal dimensions of 15 feet length. Is that enough for your car? I have an old Volvo, and it’s  almost 15 feet long. You obviously need a bit of space at the front and back. 

MikeJXE

I was a builder, it depends on the construction of the conversion 

If it was a double garage with a double garage door (I’m guessing it was) and it still has the original concrete  floor plus the interior walls are stud (I’m guessing they are)

Then it wouldn’t cost much at all depending on what door you choose 

Me <5k

Flugelhorn

Good idea to look into this - often think the rooms created look just like a converted garage, don't get the feeling there is any premium on  buying them, the extra "rooms" don't add much 

Flugelhorn

GDB2222 said:

ended timber floor, and the original garage floor is intact underneath?  Also, what finish do you want?

The plan shows internal dimensions of 15 feet length. Is that enough for your car? I have an old Volvo, and it’s  almost 15 feet long. You obviously need a bit of space at the front and back. 

ha ha - all my assessments of garages are "can I get my volvo estate in?"

Section62

GDB2222 said:

...

A lot depends on how the conversion was done. For example, is there a suspended timber floor, and the original garage floor is intact underneath?  Also, what finish do you want?

The plan shows internal dimensions of 15 feet length. Is that enough for your car? I have an old Volvo, and it’s  almost 15 feet long. You obviously need a bit of space at the front and back. 

I think the oddly-shaped "outbuilding" was probably part of the original garage as well, in which case it means the area of the WC where the washbasin is probably also needs to be added back to the garage - meaning the WC would need getting rid of, or adapting to have access from the habitable space side (+reprovision of handwashing).

OP, to comply with building regulations there needs to be thermal insulation between the garage and the rest of the house, and more importantly there has to be sufficient fire resistance between the garage and the living area (this includes walls, doors and ceiling).

Your costs will depend on how much of the necessary 'garage' stuff has been removed as part of the conversion, and how 'permanent' the new construction was made.

As per my reply to GDB2222, the existing layout looks a bit odd. So the first step is to find out why the layout is as it is, and preferably what the as-built layout looked like.  For example, the squarish "storage" room between the office and playroom strikes me as odd for a garage conversion - since the 1980's most people would opt for some built-in cupboards in one of the rooms, rather than constructing a dedicated 'storage room'.  Typically on estate agent plans where they say 'storage' it means it is a space you can't do anything else with because of some physical constraint.  This is partly why it will be important to understand what was there before the conversion was done.

Are there any property listings including a floor plan from before the conversion work, or are the original planning consent drawings available online?

If 4.6m is long enough for the cars you want to keep in the garage then you'll still need to make sure that all the walls, door and ceiling comply with building regs for fire resistance and limiting the spread of smoke etc.

WIAWSNB

ignite_me said:

This is the floorplan of the garage:

It could - should - be pretty cheap. The cost of turning that garage into proper, conforming, habitable rooms would likely have been significant, as this would have required insulation, and everything else carried out to required standards.

Returning it to a garage should be pretty cheap, provided you will be happy with the internal size. I'm guessing that the section outlined in orange here is the 'garage'?

If so, I'm equally guessing that the internal walls are 'stud' and dead easy to remove - a day's labour. 

Then there's the floor. Almost certainly that will need removing to get back to the original garage floor level - again a day's labour.

And there's the refitting of the car-entry garage doors, but this should be relatively easy as the original lintels will surely have been left in place. Finally, the door into the house will need to be fire-rated.

The inside volume is likely to be less than that of the original garage, as insulation will/should have been added to the insides of the external walls. I'd only go to the expense of removing this if you really had to, because if you can keep it, then you can always sell the house onwards as one with a garage ready to reconvert into living space :-)

If you wish to increase the garage depth on the RH side by incorporating the outbuilding, I suspect that will be more complex, as it's likely to be a structural wall.

Cost? No idea. But start adding up the costs of the new doors, and then labour!

Section62

Section62 said:

...For example, the squarish "storage" room between the office and playroom strikes me as odd for a garage conversion - since the 1980's most people would opt for some built-in cupboards in one of the rooms, rather than constructing a dedicated 'storage room'.  Typically on estate agent plans where they say 'storage' it means it is a space you can't do anything else with because of some physical constraint.  This is partly why it will be important to understand what was there before the conversion was done.

Thinking about it, the layout does mean the 'office' could also be used as a downstairs bedroom, in which case the 'storage' room may have been intended for later conversion to an en-suite/wetroom, hence having a door to the office rather than the playroom.  Being adjacent to the WC also then makes sense for access to plumbing and drainage.  Just a guess though.