Detached garage modernisation/conversion advice

[Woodchip Wilbur]

Looking at the picture it appears that no guttering is used on either yours or the neighbouring garage so the gap between the two must get completely saturated when it rains, I'm not surprised there's water coming under the wall. If you use it in it's current state then I would try and at least address that otherwise it will always be damp. Trouble is it involves the neighbour which can extremely variable....

+1 for that. If it were mine: I would rebuild a tad wider - take in as much of the path as you can get away with - the building is quite long and thin. If the "party wall" is replaced where it is, you could add your own guttering to catch the neighbour's drips if that made it easier - but, with the walls where they are, remember that access for maintenance is probably more important. I suggest that, if you are building a wooden hobby room (good word!) that access for maintenance is essential.

 

[Richard_C]

Could you build it with a sloping roof (towards your side) rather than a pointy one, then the gutter is yours alone. You still have potential splash from unguttered neighbour but all of your run off is controlled.

 

[Persephone]

I've got one just the same (except for the 'wig') and it's coming down soon as I'm building a new one. Up to now I've suffered badly from damp just like yours. It has ruined tools, cupboards and timber.

Assuming you've decided to put up with it until the house is renovated my advice for the short term is to spend a little money on keeping the damp out. Put an OB1 black sealant bead between the concrete slab and bottom of the garage sections, it can be applied over damp concrete; do this inside and outside. Also definitely fit guttering. Remove the wig if the roof underneath is still solid and undamaged; it is likely to be asbestos cement which is safe as long as it's undamaged but all that dead bramble will just be holding moss and debris which in turn is holding water.

If your budget can stretch to it fit some insulation foil to the inside of the roof to prevent condensation which will otherwise drip everywhere. You can do this using battens fastened to the inside of the metal trusses with tie wraps then staple the foil insulation to it. It doesn't have to be expensive foil, get the cheapest to prevent condensation.

I hope this is useful

Thanks Mike. I will have to put up with this garage for a while so will take your advice and try to seal it from the elements. I won't be able to get the sealant between the garages but hopefully if I put some guttering between both roof lines it'll stop the worst of the water ingress.
Good luck with your project. You'll have to post a build series.

 

[Persephone]

A small word of advice from me, although it's already been mentioned - calling it a workshop is very likely to lead to all sorts of objections from anyone able to object, so call it a 'hobby room', 'craft room', 'garden room' or anything else you like, except 'workshop'.

G.

Thanks Gordon. Yes, I guess most people's idea of a workshop is something industrial so wise words indeed.

 

[mikej460]

Thanks Mike. I will have to put up with this garage for a while so will take your advice and try to seal it from the elements. I won't be able to get the sealant between the garages but hopefully if I put some guttering between both roof lines it'll stop the worst of the water ingress.
Good luck with your project. You'll have to post a build series.

If you also seal the inside this should stop it on the side you can't access. Yes I intend the start a thread on my build. Good luck with the garage and house renovation

 

[Persephone]

save up, knock it down, make it as big as poss and add under floor heating......
sooooooo much better....

You know I did wonder if underfloor heating was something to add as I plan to fit a kit to the house and could do an extension to the garage.

 

[Persephone]

Hi Steff
If you do decide to go with it for now I would stay away from using MDF or OSB both are a nightmare if they get wet MDF especially it just blows out, plywood even tho quite dear now is pretty resilient to a lot of grief and will last you a lot longer on the electrics I did all mine myself then got a proper electrician in at the end to test it and certificate for me a lot cheaper good luck to you whatever you decide
Rodney

Hi Rodney, Good point. I was planning to use MDF for its sound insulation properties but as you say, if it gets wet it disintegrates. I would hope that any structure I build to replace this would be waterproof but I'll bear in mind what would happen if water does get through.
I can't find the post now but I read somewhere that PIR insulation acts as a noise amplifier and Rockwool dampens sound. As the garage is close to the house and neighbours house I need to be mindful of the sound of machinery.
I would consider myself fairly competent regarding electrics (my background involved some overlap) but I'm not qualified as an electrician. I will read the latest regulations when I get round to fixing the electrics and pay the electrician who does the house rewire to check it over.

 

[Persephone]

Drifting off topic I know:

That seems sensible, but its worth looking at Ikea designs in one of their showrooms just for ideas. Their cupboards/cabinets go almost to the wall rather than having the usual 2 inch or so gap behind the back panel. That brings some potential difficulties - you can't run pipework or cables behind - I ran the pipes down in one corner and along at plinth level and channelled in a short lenght of 30a cable to the hob. The drawer runners are slim and sit below the drawer sides - a lot of other types run in channels at the side. So for a given cabinet size you can get quite a lot more internal room than some older mass market ones. I installed one 12 years ago, still going strong.

If I were doing it now, being retired rather than trying to fit it at weekends/evenings I probably would make my own, but I would still steal some ideas from Ikea and wherever else I could. The price of timber and board might make me change my mind when I got to the cost calculation.

Back to garages. A new estate near us in Cambridge got in the news a few years back, with pictures of (un) happy new house owners getting their Ford Fiesta in the garage but being unable to open a car door to get out. "We complied with Government guidelines" said the builder.

Hi Richard, Good point about the Ikea cupboard backs. I remember assisting my parents to assemble an Ikea kitchen about 20 years ago (it's still going strong) and thinking how useful it was to have that extra storage space. However, as you say, pipes can be a challenge. I think if you're building the cabinets yourself you can design pipe conduits into the build.
I discovered that Ikea euro hinges are actually Blum so I popped to the Warrington store last week and bought 20 pairs as they were on sale for £3 a pair! I marvel at the way IKEA kitchens make use of space and I'll definitely look at them for inspiration.
Hopefully wood prices will begin to fall now people have started spending money on holidays (at least the people I work with have) rather than ploughing it into renovating their homes - and given the number of people who seem to have destroyed the character of their 1930s English vernacular semi by covering it in spray-on concrete it hasn't come soon enough! And throw in the problems that Chinese construction company has they might also stop buying up the world's supply of wood! Fingers crossed well soon be able to pop to our local woodyard for a nice piece of cabinet grade ply for £50.
I've seen news items on similar garages. Some builders have no shame! I live in a converted warehouse in the city centre with two floors of car parking in the basement. I can only just get my CRV into the bay and when I first moved here 20+ years ago I destroyed the bumper of my car trying to reverse into a space. But then this was built in 1907 and car parking wasn't dreamed of. The basement probably had boys pushing barrows!

 

[Persephone]

If you’re planning to remove the thatch from that roof you’ll need to be careful. It’s possible that the plants will have air roots which have grown out of the stems and bedded themselves into the roof material (which could be asbestos, as others have already said). If you pull the thatch off the roof the air roots could bring some of the roof material with it, causing the surface to crumble and create dust, which is potentially asbestos dust.
It’s an exciting time for you though, enjoy!

Hi Allen, thanks for pointing that out. It's really important and I hadn't considered it. I might spray the roof with water as I'm removing the bramble. And wear PPE!
I really can't wait to complete the purchase (I've no idea what makes it take so long) and begin to set up the machinery I've bought over the last few months.

 

[Persephone]

I'm a retired builder and agree that you need to start again as soon as it's possible to do so, your tools and machinery will rust badly if you stick them in there.

Go with temporary roof insulation and ideally a membrane to combat roof condensation which will increase as soon as you seal any drafts and air flow in the building and you would urgently need to sort the water ingress at floor level, looking at the pics that's being caused by the concrete path at the side and probably whatever is at the back of the garage as the path is higher than floor level, at very least you should clear any existing channel between path and building or cut a new one and direct water away from the building as much as possible, it might help if you can tank the lower part of the panel with bitumen or even a plastic sheet or DPM for a temporary measure, there are several methods that will help. Gutters will definitely be an improvement also as mentioned.
That also applies when you eventually construct a new building. as the path will be just as much an issue.

Hi Lons, thank you for your professional assessment, I appreciate it. I did wonder if a channel needed to be created between the raised path and the garage sides. I had planned to keep the path but perhaps in the (probably distant) future I'll remove it and lay flags on the other side of the garden. I guess that when I remove the garage I could seal in the side of the path. I'm not sure what's at the back of the garage - I think the concrete extends up to the raised patio area. I'll have to get professional advice about how this will interact with the workshop I build to replace the garage.
I like the idea of temporarily tanking the lower half of the garage to protect my tools and machinery. I've spent too much money on them to watch them rust! What would you advise to do this? I did see someone convert a similar garage and they painted the walls and floor with PVA but I'm not sure that would be enough in this case.

 

[Persephone]

We bought a bungalow to do up end of 2017. There was a small single brick garage attached, which although in OK condition was to small. We decided to wrap a larger building around it and applied for planning permission for a garage hobby room that would come 3m forward of the existing structure and 5m forward of the building line and got it passed without any issues. If you word things correctly it is surprising what is acceptable.

ColinView attachment 126160View attachment 126161

Hi Colin, Thanks for the information. Your garage extension looks impressive! I would love something that large but I don't have room for it because the driveway was built when cars were the size of modern pushchairs. But if I could build a dual skin structure like yours I wouldn't consider anything else. You'll have to post build photos on a separate thread to inspire people.

 

[Persephone]

+1 for that. If it were mine: I would rebuild a tad wider - take in as much of the path as you can get away with - the building is quite long and thin. If the "party wall" is replaced where it is, you could add your own guttering to catch the neighbour's drips if that made it easier - but, with the walls where they are, remember that access for maintenance is probably more important. I suggest that, if you are building a wooden hobby room (good word!) that access for maintenance is essential.

Hi Wilbur, The documents from the solicitor state that each house is responsible for the party wall on the left. Therefore, I think the neighbour has used their garage as part of their responsibility for the party wall. (We seem to have drawn the short straw and have the responsibility to maintain an entire length of fence between our house and the attached semi!)
When I build a new workshop (hobby room) I will likely build it from wood and as you say, this will need maintenance and I will need to access it.
For now I'll try to secure this as best as I can and will seek people's advice when it comes to the new build.

 

[Persephone]

Could you build it with a sloping roof (towards your side) rather than a pointy one, then the gutter is yours alone. You still have potential splash from unguttered neighbour but all of your run off is controlled.

Hi Richard, that's a good idea. It makes the new build much simpler too. I think the wall of the neighbour's garage is at the edge of the boundary and they used it as part of the boundary fence. So I guess I could attach guttering to their garage as technically it drops onto my garden.

 

[Lons]

Hi Steff
It's difficult to say what to use until you get at the cause but it's of little use painting the inside with PVA, you need to prevent water ingress at source from the outside so clear out or dig down a channel and for temporary solution at least I'd just run some damp proof membrane (DPM) vertically up the wall and make a fold at the bottom away from the wall ideally go deeper than the edge of the found or slab and even better if you can get at the wall and paint with bitumen before placing the DPM. Backfill on top of the DPM channel with pea gravel if you can and most of the water will be directed away past the garage. DPM degrades in UV but the pea gravel will prevent that and it will last a long time.
Remember however it has to go somewhere so you likely need to direct it away from the drive and house or it will pool and maybe cause other issues depending on how much there is of course.

 

[Persephone]

Hi Steff
It's difficult to say what to use until you get at the cause but it's of little use painting the inside with PVA, you need to prevent water ingress at source from the outside so clear out or dig down a channel and for temporary solution at least I'd just run some damp proof membrane (DPM) vertically up the wall and make a fold at the bottom away from the wall ideally go deeper than the edge of the found or slab and even better if you can get at the wall and paint with bitumen before placing the DPM. Backfill on top of the DPM channel with pea gravel if you can and most of the water will be directed away past the garage. DPM degrades in UV but the pea gravel will prevent that and it will last a long time.
Remember however it has to go somewhere so you likely need to direct it away from the drive and house or it will pool and maybe cause other issues depending on how much there is of course.

Hi Lons, Thank you for replying. I apologise for the delay in responding - I contacted Covid and became quite unwell (thanks Mum!). I really appreciate your response. I have an angle grinder so I will cut away some of the concrete path that runs alongside the garage and place some DPM along the side of the garage. I will try to direct run off to the main drain.
When we pull up the floorboards to add insulation we will be able to see if the sloping garden has led to any erosion of the soil under the house.
I also thought about painting the inside with some bitumen waterproofing before boarding it out.
Thanks again,
Steff

 

[Lons]

Sorry to hear about the Covid, we've managed to avoid it though my brother was infected 3 days before Christmas and it knocked him for 6. He had all 3 jabs so probably would have been much worse if not vaccinated.

If you can get hold of a length of field drainage pipe to lay at the botton of the trench you cut it will be more efficient than just pea gravel though still needed on top and even better to put in a layer of permeable fabric on top, it's very cheap

 

[Persephone]

Sorry to hear about the Covid, we've managed to avoid it though my brother was infected 3 days before Christmas and it knocked him for 6. He had all 3 jabs so probably would have been much worse if not vaccinated.

If you can get hold of a length of field drainage pipe to lay at the botton of the trench you cut it will be more efficient than just pea gravel though still needed on top and even better to put in a layer of permeable fabric on top, it's very cheap

I'm triple jabbed too but it knocked me for six. I dread to think how ill I would have been without the vaccine.
Thanks for the advice. I will do as you suggest. Hopefully I'll get a couple of years out of the garage before I have to rebuild it.

 

[Spectric]

Rather than messing about with the old garage and trying to make it watertight just put a tarp over it and tie down, or slap a coat of this over the roof Flag Roofix 20/10 Roofing Repair | Instant Waterproofing

which will also help if that roof is asbestos by stopping it making dust on removal.

 

[Persephone]

Rather than messing about with the old garage and trying to make it watertight just put a tarp over it and tie down, or slap a coat of this over the roof Flag Roofix 20/10 Roofing Repair | Instant Waterproofing

which will also help if that roof is asbestos by stopping it making dust on removal.

Sorry, I don't know how I missed this. Thanks for the reply. If I keep the garage temporarily I will get some of this.

 

[BenS]

If you have the funds I would rebuild.
If not get new electrics and a raised floor