To convert garage to garden room or not

[WakeMeFriday]

We live in a modest size 4 bed house. We have 2 DC 1 & 4 years old. FIL stays with us for few months. He uses the spare guest room. Baby is still in our room, older DC is in his room. We both work from home for a good part of the week.
We have a detached brick garage in garden which I want to convert to make a garden room. It will cost us around 10k. Our house is already at the area's ceiling price, so don't know if spending this will add any value.
I called council to check if we need any permission and due to the size of it, they said no permission will be needed. I have the 10k saved to use.
DH thinks we don't need more space but I feel I want to have additional living space, which will be a quiet space I can work from. Also, another consideration is that we might move house after 5 years, so that makes me think of I am wasting money. I also want to start a business and I am thinking of storing the boxes there but it's in future now right now, so can't justify that to DH.
What would you do in my situation?

We aren't desperate for space as we still have our bedroom and a bedroom we use as office.

If the garage is unable to fit a car, difficult to access, then possibly, but DH would not look at a house without a garage / workshop, so it depends. Would £10k make it a usable space all year round, so warm in winter / cool in summer?

£10k doesn't sound like enough money to me for the conversion. Heating, insulation, window, door, electrics, lighting etc.

Do you need to convert it if you might ultimately use it for storing boxes?

Where will you put all the stuff that's currently in the garage?

You might not need planning permission but you do need to involve building control unless it’s a very small building.

Realistically, your second child is going to need their own room soon so that's all your bedrooms accounted for if you need the guest room for a regular visitor and it can't double up as an office.
Personally, I would want some of the garage space for storage. I can't really see a room across the garden getting used much as an additional living space, particularly with such young kids, but can see the attraction of an office space away from the house.

I don't know anyone who uses a garage for a car.

There are 5 people already in a four bedroom house and two of them WFH. I'd say you really need more space. I'd get a shed for storage and convert the garage. There is no such thing as too much space IMO.

I know we will have to give a bedroom to our DC. That's a reason I am thinking of converting the garage to an office space, where me or DH can work from. We have got an office desk in our spare bedroom currently. I am wondering if it will help increase the value of house?

We are planning to covert ours, literally just going to fix the leaky roof, change the rickety rusted old garage door for proper doors, insulate it and board it and decorate. It already has electric (lights and sockets) and water (previous owners used it as a utility with washer/dryer in - not that thats needed anymore) and part insulation etc... My budgets about half yours and half that will be the new roof.

No planning needed as its not a habitable space in the house. If it was a habitable space like a bedroom it would be more like £20k and a lot of planning and fire safety etc... but I just need a space that gives me somewhere to use as a workshop, theres basically no real rules on decorating your garage to make it a nicer/more comfortable space to work on stuff in.

@housethatbuiltme did you get any quotes? We are in Midlands and seems it's more like 10k.

Forgot to mention we have electrics in there already.

I'm in the north east so possibly a bit cheaper (I know the closer to London the more expensive).

The roof will be £2k, the doors are coming in anywhere between £800-1.5k (depending on type and how fancy, probably going to be around £1k) and then £1.8k for boarding and skimming the walls and ceiling. Then other costs are just the paint, insulation panels and flooring all of which we will do ourselves so no quotes on that would just be picking and tailoring to our taste/needs.

I'm not faffing on installing gas central heating/radiators as I don't see the point, we already have an electric fan radiators we use that work fine.

Won't you need lighting and electric sockets?
Ignore me! Didn't read the post properly

I agree it’s a good idea.

4 bedrooms.

1 you and DH
2 dc1
3dc2
4 FIL

5th room for use as an office - and it’ll help you separate that going to work from being at home feeling.

My DB and SIL both have jobs that they work from home in and have a huge summer house (replacement as knocking down their garage) in the garden which is an office space one side and storage the other.

They said it means they feel like they are going to work even if home is 15m away! They also said it makes them feel more productive which I think for MH reasons is very important.

You get to step away from the house and toys and aren’t next door to your bedroom whilst also being at work!

A lot of people who convert their garage need to store all the stuff they currently keep in their garage somewhere else. Either a shed or retain some of the garage. The easiest way is if the garage door is an up and over, then most people keep that short front section for storage and they don't have to replace the door. You could try putting everything to the front and seeing how much space you have behind to convert.

The wall is then built behind the space left at the front. Consider the view you want especially if the garage has no door or window at present. Planning is usually for change of use but as the council said you won't need that you will still need building regs, consider that regs are the lowest standard so insulation should be as good as you can get both in the walls, ceiling and floor. You want to spend money first and not spend more money trying to heat the space all the time.

The vast majority of people do not store their car in their garage because they are simply too small to fit a car in. It is a good idea to have a separate space for working as it does feel like you have a divide between house and office.

My sister has a garden office, they have plug in electric radiator on a smart timer socket they can control from the house so if it is nippy in the morning she can preheat the office. Insulated plaster board is a good shout. Doors/windows look at ready made not made to measure which are just as good but cheaper as not bespoke. Anything you can do yourself to keep costs down like decorating, laying flooring etc.

I think it is worth doing if you still have space to park your cars because off road parking is desirable. Even if you plan to move, sometimes it doesn't happen so don't always think of getting your money back, think more along the lines of let's make this property work for us, now.

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