Self build garage project

[ilovewilly]

I'm planning on extending my single, pitched roofed garage to a triple, and I'll be using this thread to document and ask for advice along the way from those in the trade etc.

Now, I'm only in the initial stages of designing and estimating material costs. I may well end up scrapping the self build element if I can have the shell done by a builder for a reasonable amount - but cost may well dictate that I have to 'have a go' without any previous building experience. YouTube FTW.

The existing garage single skin and attached to the side of my house. I will be retaining the existing building and adding
5.2m x 5.2m Total area – 27.04sqm.

A triple garage attached to the side of a house on a suburban housing estate may look a bit intrusive, so I'm considering how I am going to place doors to the front. The image below shows scale with 3 standard single garage doors. *note the internal wall is the existing external wall, and would be removed. I've left it in for scale so I can picture the area split in to the single size.

I drafted that up on floorplanner.com. I really need to grasp something better like SketchUp.

My other option is to perhaps leave that internal wall in place, to add separation to make it possible for a future home-owner to have perhaps a utility with a double garage attached - which would save me demolishing, removing the material and would enable the existing space to hold my belongings whilst work is under way, unless I removed it at the end when watertight.

3 doors, all singles does look a bit like a block of garages. So I considered having a solid wall to one side and two single doors.

My house is brick with a rendered porch, so I'd be tempted to render the outside to tie it in, and arguably it may well be cheaper than facing bricks plus it covers up DIY block laying with half arsed messy pointing. Thinking back to my earlie thought of making the build future friendly, I have considered blocking up my exiting garage door and leaving the internal wall with a double to the side so it looks as if its a utility with a window to the front - with in reality a car shuffled over to the side on go jaks or using that left side for storage/workbench.

I won't bore people just now with my initial material quantity and cost estimations. My initial assumptions are that I can build this using single skin, 100mm block work. I don't feel the need/expense of making it double skin, insulated. Due to the upstairs layout of my house I can't see me ever building up. I've no current damp issues to report with the existing single skin garage.

Any considerations or queries appreciated to get me thinking and help improve the end product.

 

[Steve]

Contact your building control, they will tell you what you can & cannot do.
You may need planning you will need building regs.

 

[ilovewilly]

Contact your building control, they will tell you what you can & cannot do.
You may need planning you will need building regs.

Agreed. I want to finalise my plan with the minor details decided before I go to them so I can do it the once.

I know I'll need to meet building regs and have control check it at the various stages. Due to the size and overall height, I should well fall under permitted development opposed to planning - again I'll know for sure when I approach them with the final intentions.

 

[LeeRS]

Instead of having 3 singles, or 2 singles and a wall, why not have a single and a double?

Would be a pain in the arse to get a car in and out of a single door when there is space for a big double.

Regarding the internal wall you are planning to take out, why not have a store room (so to speak) in the original garage and have all workspace in the other side. Im presuming you are using the double to work on cars.

 

[Steve]

Don't forget windows, veluxes & plenty of insulation.
Wants to be light & not cold.
What's the rest of the street got re garages?

 

[Chris V6 255]

I would leave the single garage as it is and add a double to the side. 1 X single garage door & 1 X double garage door. Leave the internal wall in so it can be used as a storage area.
Add an internal door from the single garage / store to the double garage.


Sent from my iPhone using Tapatalk

 

[ilovewilly]

Instead of having 3 singles, or 2 singles and a wall, why not have a single and a double?
Would be a pain in the arse to get a car in and out of a single door when there is space for a big double.
Regarding the internal wall you are planning to take out, why not have a store room (so to speak) in the original garage and have all workspace in the other side. Im presuming you are using the double to work on cars.

I would leave the single garage as it is and add a double to the side. 1 X single garage door & 1 X double garage door. Leave the internal wall in so it can be used as a storage area.
Add an internal door from the single garage / store to the double garage.

I hadn't really considered a single door as well as a double door. Probably due to aesthetics. The width of a single door doesn't really concern me from an entry point of view.

The reason I may not want to keep the brick internal wall is because that does leave me with 'just' a maximum usable space of a double garage. It could be limiting for working and moving around 2 vehicles, whereas if the wall was gone, a vehicle could be shoved right against the wall to the side of the house, and leave a double garage width, plus near on a metre of space which would give more room for opening a door.

I had pondered about perhaps building a wooden partition in place of the brick wall, but perhaps set in a bit more, to give me the mentioned storage room but smaller, leaving a double and half perhaps. That would be dependent on the door situation I guess as it would be silly to have a single door to the left, which you open to a partition splitting it.

Appreciate the thoughts though, gets me thinking.

Don't forget windows, veluxes & plenty of insulation.
Wants to be light & not cold.
What's the rest of the street got re garages?

Window wise I was probably going to go for a reasonable sized one on the back wall, looking out to my garden to get some light in, which would be against the boot/bonnet of a car and thus not be in the way of workbenches which would be to the side of the garage. I considered some high rectangular windows to the right side, but there is a house about 5 metres of that and it may not get the best light. I'm not going to fit a velux roof windows. I'd probably board the loft anyway for storage - the current garage is boarded and has been handy to date. I'd have to be clever with natural lighting.

Existing garages are mostly singles attached to the side of houses or link detached houses with 2 garages between. I do have the second largest plot of the estate though, hence the reasonable side return.

 

[Budgie]

100% go for a double sized door. I can do electric rollershutters very cheaply supply only. Also can do windows and resi doors should you need those too...

 

[Archtronics]

Got a plan of how it will look next to the house?
This should help determining if you will need Planning permission https://www.planningportal.co.uk/info/200130/common_projects/43/outbuildings

 

[ilovewilly]

I think I am going to need to go down the planning application route due to the width.

Permitted development states a side extension can have a width 'no more than half that of the original house.'
My property is 7.42 metres wide (this includes the single garage which was built at the same time as the house) and the extension I propose is a shade over 5m - so regardless of whether they would include the original single garage width - the size is over half and I don't want to resort to limiting the size to make the difference between permitted and gaining permission.

I attempted to use Sketchup to mock the design against the house and made a pigs ear of it so will need to give my sketch to someone to draw up on a PC.

Existing site plan, and proposed:

(You think they are bad - I've actually seen people submit stuff of that standard for approval!)

The boundary on the right is at an angle. On that side, the site is unlevel. It's effectively sunk to a slope. This has long been a concern so I need to look in to that. The house opposite me has a brick wall to the garden which has also sunk. The plans from when I purchased the property suggest it's infilled land. There is a brook a couple of hundred metres behind the house so I imagine it's a ditch that's been filled in and sunk over the years (late 80s build). Crosshair is on my property.

I have contacted the water board to see if they had a decent site plan. I hope they have more than just the mains feed and sewage. Ideally I want to see where the drains run from the existing garage etc. This is what I have from the search pack when I bought the house:

The mapping request part of their website lists very similar as an example plan - so I'm not holding my breath. Perhaps someone on here will be able to advise on the likely hood of it being a detailed plan of my site alone l before I pay £18 to receive exactly the same plan again. Maybe the council are the people to ask for when the house was built.

 

[mace¬]

The only advice I can offer is bury the Mrs when you are laying the new garage concrete floor, it will save a lot of hassle later on when she is nagging you to do s**t and haven't got time to do anything in your garage.

 

[ilovewilly]

2 years ago? - the time flies. Things get in the way etc etc.

No progress to report unfortunately, although this idea is near the top of my wish list so I have been considering the design again.

Here’s the existing single garage and the 6M space to the side

I had concidered a 14 foot wide door, attached directly to the right of the existing garage outer pillar, but a 16 foot door would allow me to drive two cars in alongside each other with ease and leave a reasonable gap betweeen. A 14 foot opening may be a bit tight if I had one running vehicle and one that was immobilised next to it.

A 16 foot wide door doesn’t mean I would have to move the opening over to the left and lose the existing gabel wall, which is probably actually a benefit from an access point of view plus it allows me the depth to add cabinets down each side without protruding past the opening.

Here is a mock up I drew quickly for a builder to look at to give me an indication of cost.

The spec given was:

Single skin blockwork 5 metres wide and follow the original depth which is about 5.5 metres. Rendered exterior. Tiled pitched roof to match original. Gives me an overall width of 7.7M.

Remove existing gable end wall and match existing garage floor height.

Steel lintel for a 16 foot wide garage door and brick up existing single garage doorway and add a window.

Add a personal door the side and a window to the rear wall.

The ball park estimate is 15-18k inclusive of VAT and removal of all waste. Doesn’t include any electrical works, just the shell. Also doesn’t include the garage door as I figured I may as well arrange that myself - @Budgie could do with a estimation on an electric roller door if you have a rough idea please


I’m unsure at the moment whether that’s a competitive estimate or not. Will get another quote or two to see where it sits.

Still considering getting someone in to do the groundwork’s and then employ a bricky and roofer myself in stages and labour where necessary.

Obviously this is all subject to appproval. Need to speak to building control to understand more about how that works.

 

[ilovewilly]

Another 18 months or so pass. Finally submitted an application for planning.

Here’s what I applied for in the end. Drew these myself so be kind

Should hopefully have a decision in the next 4/6 weeks. Fingers crossed.

 

[Archtronics]

Be interesting to see if they pass it usually they get a bit funny about changing the principal elevation, Good luck!

 

[Cub.]

Be interesting to see if they pass it usually they get a bit funny about changing the principal elevation, Good luck!

This. I wouldn’t be surprised if they reject it because of the disproportionate nature it will create to the frontage.

What’s the rest of the street scene / frontages like to the left and right? All the same kind of house / garage? Or a mix of loads of different age houses / sizes?

 

[Cub.]

Also, what was driving the need to submit planning? Is it over the size of single story permitted development or breaks the “percentage increase rules”?

If it is, sadly, that’s an indicator it will struggle, as the permitted development rules are a pretty good indicator of what ratios will be acceptable.

 

[ilovewilly]

Be interesting to see if they pass it usually they get a bit funny about changing the principal elevation, Good luck!

it’s set back from the front of the house and the house to the right is built about 4 metres or so from the boundary. No windows or anything to that side of their property.

Agreed the width is very much chancing my arm, but in for a penny...

 

[ilovewilly]

This. I wouldn’t be surprised if they reject it because of the disproportionate nature it will create to the frontage.

What’s the rest of the street scene / frontages like to the left and right? All the same kind of house / garage? Or a mix of loads of different age houses / sizes?

All the other garages along the street are either on the end like mine or link detached. None are doubles along my road. An adjacent road had a large detached double garage seperate from the house to the front garden, so I am in hope that they don’t believe it affects the street scene too much, but I do know I am pushing my luck.

 

[scullyg40]

View attachment 160806

Extend the section a bit more to the back, so you can enter it from the area which is also the entrance to your existing garage.

 

[ilovewilly]

Also, what was driving the need to submit planning? Is it over the size of single story permitted development or breaks the “percentage increase rules”?

If it is, sadly, that’s an indicator it will struggle, as the permitted development rules are a pretty good indicator of what ratios will be acceptable.

The additional footprint is 27sqm, so beneath the 30 for permitted development but due to the ridge height and being 1050m from the boundary at the closest point (boundary is at an angle going away to the rear).

 

[Archtronics]

it’s set back from the front of the house and the house to the right is built about 4 metres or so from the boundary. No windows or anything to that side of their property.

Agreed the width is very much chancing my arm, but in for a penny...

Well If you don’t get the full width and only get a double garage you can always stick a decent carport on the end under permitted development after the fact.

 

[eugegall]

Is that a square plot?

or does the right hand boundary as you're looking at the front of the house, come in at an angle?

 

[eugegall]

Just looked at plans and street view etc!

You would be crazy not to put planning in for another little two bedroom house on the end.

Profit would help pay off some or all of the mortgage you have left on yours.

Considered that?

 

[ilovewilly]

Well If you don’t get the full width and only get a double garage you can always stick a decent carport on the end under permitted development after the fact.

Yeah, aim high and see what compromises I may have to make.

Just looked at plans and street view etc!

You would be crazy not to put planning in for another little two bedroom house on the end.

Profit would help pay off some or all of the mortgage you have left on yours.

Considered that?

I certainly have. There’s enough width for it, although at the expense of me losing some garden and driveway space so that plan would probably lead to selling both. A neighbour in a nearly cul de sac did as you suggest.

 

[Matt76]

I think that would go through, as long as the neighbours don’t complain. Or they may make you change it slightly and submit it again they have a habit of doing that.

 

[ilovewilly]

Update time.

They wrote to me a few weeks ago stating:

“The width is considered to be excessive in relation to the main dwellinghouse and should be reduced....I would be grateful to receive amended plans, showing a reduction in the size of the proposed garage.”

Gave them a call to understand how much it would need to be reduced, as it wasn’t clear exactly how much I was pushing my luck. Local guidance suggests that a car parking space should be 3m wide, so a double garage should be around 6m in width. I explained my reasoning for wanting to make the most of the the width available and that 6m wide would be a compromise.


And today, permission was granted

 

[Cub.]

He shoots.....he scores!

 

[seb]

Update time.

They wrote to me a few weeks ago stating:

“The width is considered to be excessive in relation to the main dwellinghouse and should be reduced....I would be grateful to receive amended plans, showing a reduction in the size of the proposed garage.”

Gave them a call to understand how much it would need to be reduced, as it wasn’t clear exactly how much I was pushing my luck. Local guidance suggests that a car parking space should be 3m wide, so a double garage should be around 6m in width. I explained my reasoning for wanting to make the most of the the width available and that 6m wide would be a compromise.


And today, permission was granted

you got what you submitted originally or had to compromise on just six metres?

well done though!

 

[ilovewilly]

you got what you submitted originally or had to compromise on just six metres?

well done though!

Got what I originally submitted - going from a 2.7m wide single to a 7.7m double.

Now I’ve just got to clear the site and think how much I want to do myself. Guess I’d like it done for the winter, so will need to crack on and see what the situation is with materials and labour

 

[ilovewilly]

After several months of waiting for a ground worker to come in, the dig started on this today.

Oh boy it soon escalated. A French drain was discovered under the rear footing which runs under my garden.

Comes out through the front and beyond. That’ll probably have to be diverted which’ll cost me. Small glimmer of hope it’s redundant, but unlikely.

Neighbours bay tree has meant going from a 900mm footing to over 1.7 bloody metres. That’ll bloody cost me an all. Doesn’t look that deep in a photo.

Won’t have any money for cars to store inside at this rate

Saga continues tomorrow.

 

[Rob]

Not the best month to start ground works, but keep us updated! Keep the pics coming and posting any problems, always interested and happy to lend an opinion if I can!

 

[ilovewilly]

Agreed - been hanging on and hanging on for this chap as I’m impressed with his work so was happy to wait as a decent contractor is rarely able to fit you in quickly.

I’m happy if I just get up to DPC before the weather turns and wait until next year to get the walls up.

I’ve built this thing 27 times in my head trying to allow for this and that and not once did I expect to find that drain under there.

What’s your speciality Rob?

 

[Rob]

Agreed - been hanging on and hanging on for this chap as I’m impressed with his work so was happy to wait as a decent contractor is rarely able to fit you in quickly.

I’m happy if I just get up to DPC before the weather turns and wait until next year to get the walls up.

I’ve built this thing 27 times in my head trying to allow for this and that and not once did I expect to find that drain under there.

What’s your speciality Rob?

Construction design and project management generally. I’m a design/project manager for an engineering consultant, background is mostly arch/elec however.

Looking at that drain... can you not do a build over as opposed to a re-route? However if it ever went wrong it could get expensive...

 

[ilovewilly]

Construction design and project management generally. I’m a design/project manager for an engineering consultant, background is mostly arch/elec however.

Looking at that drain... can you not do a build over as opposed to a re-route? However if it ever went wrong it could get expensive...

Interesting to know.

Good time to mention this is a single skin 100mm block building and last week I suddenly decided it may be an idea to try and go 2 storey at some point - but rather than change the plan and go 600mm wide trench and double skin to never get the permission/change my mind I am cracking on and will in time potentially put in for that and if successful try and add steels to make the second story a double skin with a timber inner skin - I know you’ll call me mad for making work and expense for myself.

I’m not entirely sure how it would be built over - I’m all ears as I’m unaware of the method to do so. Build a bridge over it?

Caught the grounworker and BCO talking of adding a solid pipe inside and digging up 5 meters of my driveway to thread the bloody thing in so I’m not keen on that idea.

Initially I thought can’t you just cap each end where it lays under the driveway/garden and when any water runs in it, it will disperse either side without going under my garage slab.

 

[Rob]

Interesting to know.

Good time to mention this is a single skin 100mm block building and last week I suddenly decided it may be an idea to try and go 2 storey at some point - but rather than change the plan and go 600mm wide trench and double skin to never get the permission/change my mind I am cracking on and will in time potentially put in for that and if successful try and add steels to make the second story a double skin with a timber inner skin - I know you’ll call me mad for making work and expense for myself.

I’m not entirely sure how it would be built over - I’m all ears as I’m unaware of the method to do so. Build a bridge over it?

Caught the grounworker and BCO talking of adding a solid pipe inside and digging up 5 meters of my driveway to thread the bloody thing in so I’m not keen on that idea.

Initially I thought can’t you just cap each end where it lays under the driveway/garden and when any water runs in it, it will disperse either side without going under my garage slab.

Any idea what it services? And what’s the depth in relation to underside of your proposed slab? Assume you’re going ground beating?

I was implying bridge it, much like you’d do for a Thames water build over agreement on a terraced house extension or similar. I’m sure I have a detail somewhere.

To be honest, whilst you have the mini digger in, why not just do a quick over dig around the outside of the slab and 45 into each piece so it doesn’t go under the new?

Not mad at all on the second story, but I’d 1000% be doing the groundwork and wall build up now. It really won’t add a lot surely?

 

[Rob]

 

[J-J]

Any idea what it services? And what’s the depth in relation to underside of your proposed slab? Assume you’re going ground beating?

I was implying bridge it, much like you’d do for a Thames water build over agreement on a terraced house extension or similar. I’m sure I have a detail somewhere.

To be honest, whilst you have the mini digger in, why not just do a quick over dig around the outside of the slab and 45 into each piece so it doesn’t go under the new?

Not mad at all on the second story, but I’d 1000% be doing the groundwork and wall build up now. It really won’t add a lot surely?

This. Do the groundwork now, steels would work but you'll be adding columns which will in turn require more foundations. Concrete is what, 100 quid a cube? A grand now could save you 10 in the future.

 

[gez 172]

As above - it’s MUCH cheaper to get the basics (foundations) done right from the word go. You’ve got the digger/builder there. I wouldn’t want to build ontop of footings that you’ve only built for a single storey. Plus, there’s a chance you’ll be refused by regs later on to build ontop of ‘substandard’ (substandard for a double) footings.

 

[ilovewilly]

Any idea what it services? And what’s the depth in relation to underside of your proposed slab? Assume you’re going ground beating?

I was implying bridge it, much like you’d do for a Thames water build over agreement on a terraced house extension or similar. I’m sure I have a detail somewhere.

To be honest, whilst you have the mini digger in, why not just do a quick over dig around the outside of the slab and 45 into each piece so it doesn’t go under the new?

Not mad at all on the second story, but I’d 1000% be doing the groundwork and wall build up now. It really won’t add a lot surely?

I was rummaging through my solicitor search paperwork trying to find a plan where it showed infilled land but couldn’t put my finger on it and then noticed I’d uploaded it in a post above, years back.

Presumably there was a ditch or something along the line when it was a farmers field. Presumably the developers chucked the drain in when they levelled the site.

The pipe is fairly level, about 8” and permeable with a load of type 1 chucked around it.

The depth to that pipe is currently about 900mm to the slab. Had it been about 100mm lower - they’d never have found it and I’d be none the wiser.

When you say add a 45 elbow to each end, where would the pipe sit in relation to the trench fill?

The build over in your drawing looks straight forward in the event this drain is still operational (likely).

Although I’ve kinda set a precedent with the single storey, I don’t have much confidence that they’d approve a full 7.7m wide top floor alongside my relatively narrow house. The floor area would almost be the existing, repeated.

If I was a betting man, they’d make me pull it in and have the top floor stop 3/4 way along requiring steel anyway. My theory is either spend a couple of grand now and never make use of it or spend 5 in time if a cheeky application gets approval.

 

[ilovewilly]

This. Do the groundwork now, steels would work but you'll be adding columns which will in turn require more foundations. Concrete is what, 100 quid a cube? A grand now could save you 10 in the future.

As above - it’s MUCH cheaper to get the basics (foundations) done right from the word go. You’ve got the digger/builder there. I wouldn’t want to build ontop of footings that you’ve only built for a single storey. Plus, there’s a chance you’ll be refused by regs later on to build ontop of ‘substandard’ (substandard for a double) footings.

My intention would be as follows, steels off the piers.

Wouldn’t be CS if the OP didn’t go ignore sensible advice