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Wall question for a garage

Dear all, I am building a garage on my plot under permitted development prior to the planning application for the house. It is going to be about 7 meters by 9meters and the architect wanted 190mm solid walls with 450mm pillars at 3 meter centres,when I questioned how thick they were he offered 140mm hollow blocks with 450mm pillars at 3mtr centres. The only other garage I built was 100mm brick with 200mm pillars at 3 Mtr centres. This seems to me to be overkill and I admit I don't have a lot of faith in the architect and will probably not use him for the house. Apart from trying another architect does anyone have advice on spec for this kind of work please?


  • It may be because of the higher windspeeds down here. Have you checked what is the minimum requirement?
  • Hi Nick, not sure hence the question for the great and good on here
  • Try this (though may be out of date), pages 23 and 24
  • Thanks Nick, pages 35 show a minimum wall thickness of 90mm and piers of 390 x 190 . This is more in keeping with what I have dealt with in the past. The wind speed pages seem only to restrict the maximum height for the building. I think I may call the Building inspector and ask for his opinion as its him who will sign it of.
  • If it is going to have a roof on it that will do it a whole lot of good in terms of bracing things and stabilising the walls.

    If you don't need building regs I would say 100mm walls with piers, I like 450 wide and 215 thicker than walls, one each side of doors and one on the 7m wall and two on the 9m wall.
  • Tony, thanks but it does need building regs but I believe 100mm block is ok with pillars like you say but they need to be every 3 mtrs (to centres of pillars)
  • I think the things with walls (and buildings in general), is not so much about what is needed to hold them up (not much really), but is for when they fail.
    One could imagine that a wall without any piers could totally topple over and say a 6 m wall with one pier may have only one 3 m section collapse, 2 piers and only a 2 metre section.
    You may find that garages need to be stronger because there is a greater risk of damage.

    I think a call to the local building control office may help.
  • The ones I have built in your area Joe have all been 100mm block with pillars @3m intervals.
  • Build it with a 200mm wide cavity wall, (ie 400mm overall) plenty of insulation and a few window positions - it might be a garage now, but in years to come it might well be a good space for an aging outlaw or recalcitrant stay at home child - or even a studio !!


  • edited April 2015
    At 7m x 9m that is a fair sized garage (as big a foot print as my old SD house!). I would do as Barney suggests. My more modest 5m x 5m new garage was built double skin both for structure, ease of build and "just in case", but no insulation. Got a good height on it too, great for storage.

    Oh yeah, if not attached to the house does it need BC?
  • Interesting that a few question the need for bc, I was told by my architect it did? And I have the plans they drew. As this is my retirement house I have no plans whatsoever of converting to further accomodation for anyone else, in fact we have scrapped plans to keep the residential caravan on site as we don't want to be inundated with lots of visitors (we have two spare bedrooms for the ones we invite ☝️
  • edited April 2015
    Posted By: joe90It is my man shed, my workshop.
    Then cavity with insulation, so you can be warm! At least cost it up. Those that come after you may be glad that you did it too.

    [Edit]You can get some "better" garage doors that are insulated and seal, more expense but make for better conditions for you and your toys.
  • As for BC
    Under the building regulations single storey detached garages and garden stores do not require consent providing the following conditions are satisfied.

    1. If the floor area does not exceed l5sq.m (16 sq. ft) constructed of any materials or
    2. If the building is sited 1 metre or more from the boundary and the floor area does not exceed 30 sq.m (322 sq.ft) constructed of any material or
    3. If the building is sited within 1 metre of the boundary and has a floor area of less than 30 sq.m (322 sq.ft) and the building is constructed substantially of non-combustible material.
    9 x 7 = 63sqm so seems that you are not exempt.
  • adi
    edited April 2015
    Just finished building my garage earlier in the year (6*10m) internal floor area. Once you get up to this size it has to meet building regs so walls need to be at least 190mm think. When I costed it out it made sense to have a 100mm cavity fully filled with insulation but should make it far more usable in the winter. I also put insulation under the floor and in the roof.

    Another item that I didn't realise to BC pointed it out was the roofing membrane on my pitched roof had to meet a certain fire classification. In reality almost impossible to find a product that meets this requiment so easiest solution was to plaster board out the ceiling.

    Looks like my old classic cars are going to be stored in nicer condition than some people live in but least it should be ok when I do some work on them in the winter!

    If you are planning to use in the winter I would definatly recommend putting in some insulation when you build it as it doesn't add much cost.
  • I think draft free is more important than insulation unless you will be using the garage for more than a few hours at a time. Then just fit a fun heater or infer red lamp.

    There are very few days in the UK, when it is too cold to work with a coat on if you are protected from the wind.
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