Big Garage Project

[GJS]

I'm planning to build an attached garage to the side of my four bed detached 1990 built house. The house is on an end plot of a close and the side I am planning to build on borders the adjoining street, not the neighbour's house. Construction will be brick and concrete tiles on a pitched roof to match in with the existing house. I'm aiming to do everything myself except the brickwork which a mate of mine will do. Tons of questions but here's a few to kick off.

Drawings - I plan to do these myself. I'm Ok with CAD software and have some background in engineering drawing, though not building drawing. Are Planning and Building Control fairly lenient on the quality of the drawings for application purposes? I've got some house extension drawings to use for guidance.

Footings - Will I need a strip type footing or just a concrete slab base?

Floor level - Does this need to be above, below or the same height as the house floor?

Chimney - The outside wall of the house that will form one wall of the garage has the fire flue from the living room on it. There is no chimney breast inside the house so the whole flue is external i.e. it will protrude out into the garage. Will this cause me any problems with regs? I'm thinking risk of gases escaping through the flue brickwork into the enclosed space of the garage?

Lintel above door - I'm planning to have a double size sectional door at one end. The pitch of the roof will come down to this door so there is effectively just the wall plate above the door. What kind of lintel will this need, an RSJ? Catnic type?

Lead flashing - I planned to join the new roof to the existing side of the house with lead flashing cut into the existing brickwork then dressed over the new roof. Then I read on here that a cavity tray may be required. Is it? Please say no!

Any advice appreciated.

 

[noseall]

cavity tray in Kent-no chance.

if you access the garage from the main dwelling then the garage floor needs to be 100mm (min) lower than the house. we tend to make them 150mm lower, as this is more in-keeping with external ground levels.

if you are building close to a public highway then planning will be an issue. they will require a basic outline plan and elevation drawings, nothing too technical.

building control don't necessarily need a drawing, you can build the extension via a building notice. if the build is particularly "engineered" then full reg's plans are wise.

i prefer strip foundations as raft slabs require lots of reinforcement and engineering calcs.

i don't envisage any problems with the chimney.

the lintel will require calc's even if it is a manufactured proprietary "catnic" type. any opening above 2m will come under b.c. scrutiny

 

[GJS]

Many thanks, Noseall.

Glad I haven't got to worry about that cavity tray lark!

So I'll make the floor level the same as the existing drive way provided it's at least 100mm below FFL in the house.

I've no doubt planning will be an issue for lots of reasons. I should be able to draw front, side and back elevations without too much trouble. I expect there will be several iterations before, or if, I get approval. I don't think there will be anything special about the build so I'll try a building notice and see what they say. I'm going to be doing all this well in advance of the build so I can suck it and see to some extent.

So with a strip footing, I basically build the walls, then pour a concrete floor inside them, is that about right? I want to try and keep the damp out as much as possible (garage will be mainly used as a workshop) so the floor would be type 1, sand blinding, DPM, then concrete. Sound right?

Thanks for your help.

 

[Mr M]

I should be able to draw front, side and back elevations without too much trouble.

When drawing elevations, I find it helpful to take some photographs of each elevation and print these out on say A4 size. You can then have this in front of you for reference, when you are doing your drawing

So with a strip footing, I basically build the walls, then pour a concrete floor inside them, is that about right?

The reference to the strip footing concerns the actual foundation that your external walls are built off but your comment is correct for the garage floor slab, which can be cast in between the walls. The strip footing and the garage floor slab are independent of each other though

 

[Richard C]

You say big garage project; if that means size, keep it just below 30 sq/m as that’s when other planning/regs. factors kick in. As noseall says, if your close to a highway, public footpath or within 1m meter of your any boundary, planning issues will probably arise; & be prepared for objections & that will almost certainly push your application before the planning committee & that’s a whole bunch of fun! If you have any trees within 5m ‘loose’ them BEFORE you apply or you could end up having to dig half way to Australia for the footings or, even worse, a tree preservation order!

I prepared & submitted all my own drawings (I used Visio) with a specification which I was intending to use for a full plans application but, in the end, I went the building notice route. I had to go before the committee but all the objectors stayed away & I got full PP for 2 extensions, roof, front & rear elevation changes I’m doing to an old property; so quiet some dramatic changes in my case. A4 size drawings are acceptable as long as they are clearly numbered & identified, they don’t have to be particularly detailed but you have to provide before & after drawings.

I had an attached, single garage passed without problems but had to remove a double detached garage/workshop I had at the front of the property to shut the neighbours up. But they don’t yet realise its only temporary as it’s fully within the guidelines & I will be re-submitting that on it’s own at some point, it’s just that I didn’t want to delay my PP; I will also have to re-locate it due to a ruddy tree! It’s also worth reading the planning & Building Regulations guides which you can access on line via the ODPM Planning Portal; all of the building regs are also available free of charge.

 

[GJS]

Good tip, Mr M, I'll take the photos and use as a guide. And yes, understood that the floor will not be 'connected' to the walls or footings as such.

Richard - Just building how I would like it, the garage would be just over 30m2. I thought that the only benefit of going under 30 was that PP was not required if the garage was also not adjacent to the highway and over 5m from the house. So I thought that as I have failed on the latter two there was no point in keeping it under 30m2. Is that not the case? For an attached garage next to a road, what other stuff kicks in if I go above 30? As you say, there will probably be planning issues and I am expecting them.

- I don't expect objections from the neighbours as it will not be adjacent to them and there is a bit of an eyesore fence there at the moment, bringing down the 'tone' of the close. I spoke to next door about it and he didn't see any problems.

- There is a large tree in the way. There are no TPOs but a restrictive covenant that says I must get council permission before removing it. I asked the council and they said "why are you asking us?" So I'm just going to remove it. Who's going to know? I have heard of the council slapping on TPOs as a result of planning apps so I will definitely remove it before I apply.

- I saw a planning officer before I bought the house and he said it was 50/50 whether I'd get permission. He then said I could always appeal. To me, he seemed to be saying that if I took it to appeal I would win. Does that make any sense?

Thanks for all your advice, gents, much appreciated!

 

[Richard C]

I think you have it covered OK, there is some other stuff about volume & roof heights etc. that may be worth checking out. Useful link here;

http://www.rotherham.gov.uk/graphic...idance+Leaflets/_adding_garage_or_carport.htm

Watch the tree covenant; I don’t know if they have similar penalties but I know of someone who was almost bankrupted because he felled a load of trees with TPO’s to gain access to a plot he wanted to build on; it cost him a fine of £6k per tree & he had to sell the plot on as he had no money left for the build!

If it goes to council committee (which it will if you get any objections) some biased members will often use their free vote to further their personal views or in the hope they can influence local policy. They will often completely ignore the advice given by the planning officer at the hearing even though a refusal clearly goes against the guidelines; this tends to be more of a problem in rural areas. Many give up at this point but if you appeal & your application is within the area covered by the local development plan, is in line with local development policy & complies with planning regulations you will almost certainly get your PP & also be able to claim back any costs involved in the appeal.

 

[noseall]

your local borough council will have a department within that will deal with current t.p.o.'s.

a tree can be self setting and immature and still be covered by a t.p.o.

 

[^woody^]

- There is a large tree in the way. There are no TPOs but a restrictive covenant that says I must get council permission before removing it. I asked the council and they said "why are you asking us?" So I'm just going to remove it. Who's going to know? I have heard of the council slapping on TPOs as a result of planning apps so I will definitely remove it before I apply.

Who benefits from the covenant? Only the beneficiary can enforce a covenant, and the council are not (and can not be) involved unless they are the beneficiary.

The council have no remit to give you permission to remove a tree, unless it has a TPO, or unless they own it, or unless it is subject to a specific condition as part of a previous planning application.

A TPO will only be placed on trees of significant interest - not just because it is 'big'

The problem with removing it, is that the ground will then become wetter, and if you build before the ground stabilises, then you risk differential settlement of the foundations.

 

[Shytalkz]

The problem with removing it, is that the ground will then become wetter, and if you build before the ground stabilises, then you risk differential settlement of the foundations.

Only in clay soils and only if the area where the foundations will be are within the zone of influence of the tree - and that would be heave, not settlement/subsidence, as the clay will swell as its moisture content increases above its natural percentage, the extent of volume increase being dependent on the heave/shrinkage potential of the clay and how far below the natural moisture content the clay was when the tree was removed. NHBC Standards 4.2 refers to mature heights; if it's not a mature tree, then zone of influence will be correspondingly less.

 

[GJS]

Thanks for all your advice gents.

Who benefits from the covenant? Only the beneficiary can enforce a covenant, and the council are not (and can not be) involved unless they are the beneficiary.

The council have no remit to give you permission to remove a tree, unless it has a TPO, or unless they own it, or unless it is subject to a specific condition as part of a previous planning application.

A TPO will only be placed on trees of significant interest - not just because it is 'big'

The problem with removing it, is that the ground will then become wetter, and if you build before the ground stabilises, then you risk differential settlement of the foundations.

The original builder is the beneficiary of the covenant. However, I believe this covenant exists because it was a condition of the original planning consent that the trees along this boundary be preserved. When I spoke to the council (or was it my solictor?) when I was buying the house, they indicated that I had no obligations under the original PP.

When I spoke to the builders (Persimon Homes) about getting permission to build out from the front of the house (I want the garage to protrude out by about 1.5m), which is another restrictive covenant, they first said that I would just need PP, regs, and no outstanding objections. They then transferred me to their archives department when they realised the house was over ten years old. When asked the same questions, they answered no, no, no and no. And no. When I persited they finally said; "...well, we don't police the covenants." So, I'm pretty much decided on ignoring the covenants as I think it's a bit far fetched that any potential buyer will know or care years into the future. I'm not planning on moving from here any time soon.

Yes, I understand that the ground may swell once the tree is removed, but not sure what I can do about it. Is there some procedure to adopt when building on or near the former position of a tree?

Thanks again.

 

[Shytalkz]

Yes, I understand that the ground may swell once the tree is removed, but not sure what I can do about it. Is there some procedure to adopt when building on or near the former position of a tree?

Thanks again.

The accepted guidance for foundations in clay soils is NHBC Standards 4.2 "Building near trees". The depth of traditional foundations in clay soils is dependent on: tree species mature height and water demand; distance from foundation; and heave/shrinkage potential of the clay, from laboratory analysis. This applies even when trees have been removed to facilitate construction and, in this instance, heave also has to be considered, due to swelling as the soil rehydrates (takes about seven years to sort itself out and return to something near its natural moisture content).

To stop the foundations moving laterally due to heave, compressible board is often required (and is required for depths>1.5m) against the inside of perimeter foundations; if the floor is suspended (pot and beam), then a void has to be maintained twixt it and the soil underneath; or if it's a suspended concrete slab, this has to have compressible board underneath. The thickness of the compressible board and the dimension of the void are dependent on the h/s classification.

If the requisite foundation depths from NHBC Standards are excessive, consider small diameter piling and rc foundation with suspended rc or pot and beam floor. Heave protection will also be required for this: pile tops sleeved, compressible board around sides and bottom of ground beams, compressible board under rc, void under pot and beam. Potential issues with this method are a) need for Party Wall etc Act procedure to be gone through, if you're within 6m of a neighbour and b) possible vibrational damage to your and neighbouring properties if percussion piles are used - alternative piling systems are available to mitigate against this possibility, but cost more. However, set this method against the cost of excavating deep traditional foundations, removal of spoil from site and loads of cubic metres of gen 1 concrete at £70+/m3 and the cost differential is, more often than not, not that horrendous.

Alternative is a raft foundation. This needs subgrade preparation and specific sub-base material importing, together with fiddly rebar/mesh fixing, but will use less volume of concrete and result in less spoil removal than for traditional foundations.If it moves, it will move bodily, with the result that the construction as a whole may go out of level, but it won't crack the superstructure. Nevertheless, that's not very helpful if attached to an existing building and it rotates away, generally resulting in a nice PI claim against the engineer. As such, not one that I would generally use, unless it's a small entirely detached garage and the h/s classification is low and there weren't loads of high water demand trees either remaining or removed within in or close to the building footprint.

I would suggest that you seek the specific advice of a local structural engineer before doing too much.

 

[^woody^]

Covenants: - the builder (Perismon) would have to be living on the land next door in order to 'benefit from them'.

If they have effectively left the area, then they can't enforce the covenant.

Developers often put these stupid things on the deeds - things like can't have a front wall, can't paint the door red etc, just to try and maintain the 'corporate style' of the development, but such covenants or terms have little legal standing

 

[Shytalkz]

Aren't they normally just put in to "protect" the housebuilder while they're still building on the site anyhow? After they've cleared off, I would assume that they wouldn't give a flying erm whatever...

 

[GJS]

Shytalkz - Thanks for this info. - though it's probably a little more than I wanted the hear! As you suggest, I will get a structual engineer to provide some guidance. I am taking down an internal wall in the house (separate project) so will need to get calcs done for a beam. I'll ask the engineer for an extra hours consulting and see what he says about the tree before I take it down. That way he'll be able to see the size, age etc.

Woody - These are very interesting points that you raise. I'll try and keep a long story short, but this is how I first heard of covenants:

A friend of mine built a porch on his house then immediately started on a rear extension, all with PP and regs ect. He got a letter out of the blue from a firm of solicitors saying that he was in breach of restrictive covenants and needed permission to do any alterations from the covenant beneficiary. It was under a different company name but the beneficiary was the same firm of solicitors. After much digging around it transpired that the original builder had sold a tiny triangle of land to the solicitors and the covenants went with them. Bottom line was that the solicitor wanted £2000 to give permission, whereas the "normal" fee (confirmed by the builder) was about £100. After much pushing back, included getting the builder's legal department to write to the solicitor suggesting he was acting unreasonably, the solicitor backed down and provided the permission at no charge.

A couple of points here;

- It seems that the builder kept his covenant rights by keeping the tiny plot of land on the estate, thus "living next door". Does that sound right?

- I don't understand why a builder would want to keep covenants for so long. In the above case the house was completed in 1970. Is it just for their corporate reputation or is it a way for the planners to pass their conditions on to subsequent owners? In the above case, it seems to me that the builder wanted rid of the rights and the solicitor saw it as a money making scheme (they had actually driven round the estate taking pictures of any extensions and porches etc. then written to everyone telling them they were in breech - w*nkers.)

May I ask, Woody, are you a legal professional? Have you come across this sort of thing before? I like what you're saying about the covenants having little legal standing, but then that's what I wanted to hear There are other covenants on my house about walls and fences, TV aerials and satellite dishes etc. and they seem to have been universally ignored by the other residents, including me when I bought the house. Nobody's been carted off to prison yet.

Thanks again for all your advice.