How to Start Building Walls; How to Build an Extension (3)

How to build a wall and how to build an extension is the latest video from Homebuilding and Renovating, in association with Folding Doors 2U. We detail the process of building a single storey extension.
With Master Builder Andy Stevens we follow the build from beginning to completion, outlining all the major stages and techniques involved.
This is Part 3 - Beginning the Brickwork, covering setting out, mixing mortar, choice of brick, laying techniques and cavity wall construction
See more expert advice at www.homebuilding.co.uk
Ultimate guide to extensions - homebuilding.co.uk/advice/extension-beginners-guide
Get the right mortar mix - www.homebuilding.co.uk/advice...
How to choose the right bricks for your project - www.homebuilding.co.uk/advice...
See more Bifold doors with wow factor here
www.foldingdoors2u.co.uk

[@neilvirgo426]

Great video. I am about to build a retaining block wall up the top of my garden and your videos are the best I have seen. thanks

[@richardmiller3998]

Great video, comprehensive knowledge but what I like most is your actually a very good presenter

[@aaronharris5275]

Really good series and loads of useful info if you are doing a DIY job or indeed wish to see what is involved and get an understanding of what the builders will do. Thanks for putting these on youtube!

[@johndavies9624]

3-1 below ground 4-1 above 😃👍

[@philipleung3108]

Very detailed. Thanks.

[@petermcgill1559]

Nice, quiet, understated way of talking. Made it much easier to focus on what he was saying, and why. Makes listening to content pleasant and informative. I can't stand people who shout or are verbose.

[@buildingvideos8426]

Excellent work mate.

[@RiderReview]

Exactly what i plan to do tomorrow. Thanks alot. You make it sound so simple and guess what if Rambo could understand you then anyone can.

[@matthewmcintyre6416]

Really good video. Really to listen and understand

[@stevenmoreno7068]

Very well explained.

[@EverydayWorkshop]

Great video thanks. I plan on building a workshop extension and your video are very clear, so thanks again Subscribed 👍

[@MrJohnnynapalm7]

Great instructional video - thanks for sharing 👍

[@HomebuildingMagazine]

Thanks Paul, good luck with any projects!

[@Zlinky111]

Great Vid. Thank you. : )

[@shawnlion4778]

I love the understanding , you're giving

[@mohammedqadeer9136]

Nice and clear

[@solo-repair9374]

Should be 3-1 mix for sub-structure [ splash course ] [ below damp ] then above damp whatever spec there is on the drawings normally 6-1/5-1. Worked on hundreds of New builds as Site Engineer

[@treepee2]

Good Video My question is:Can you come out with the foundation concrete of below ground level and make a wooden frame and level it off with same time after pouring concrete?

[@p6tan]

Nice one - a great straight to the point video. Thanks

[@OriginalPeterPan]

Excellent info mate. Decent DIY'er here and looking to build extension this year. Just subbed 👍

[@HomebuildingMagazine]

Thanks! Best of luck with the build - visit Homebuilding.co.uk for more good advice & inspiration.

[@idontthinkso2058]

3 to 1 below ground 4 x1 above Good guide though I like the reference to old school fairy liquid used by myself for many years . Well done mate good simple advice .

[@perkoshapes]

good info

[@rafalszarmacher4831]

Thank you

[@simonjohnson4004]

Great demonstration what if your measurements don’t work to block work size and you need a cut where would you put it cheers

[@TheDoobidoos]

hi can you show next adding the 50mm insulation? good vid thanks

[@lengthmuldoon]

Thought this series was great, deserves many more views. Nice work

[@deneberry4463]

Super work lads and vid ..clean work ..happy customers

[@saif1980saif]

Great video. Can you give more on the string line. How its used on inner skin. How to shift it to second course?

[@douglaslonsdale3804]

Do not use fairy liquid, use profiles for line/setting out, fill cavity up to GL with concrete to prevent ground heave. Use stronger mortar mix below DPC, gauge mortar/ container not half bag method. Could use Sulphate resisting cement ? Start face work just below ground /paving level or could use engineering bricks up to DPC/splash course. Fold DPM if concrete floor over internal walls then bed DPC on it. Tie into existing house/lap.

[@farezrbn264]

You teaching very good I want work and learn Bricklyne

[@kamgunner5920]

Hello mate. Brilliant video thank you! What part of the country do you accept work in? Thanks.

[@paulbrookman6799]

washing up liquid...I was on a site where they were using that once and building control stopped all works, better to use feb in your mortar mix

[@buildermarkdarrin6517]

Should use level buckets to knock up the mix to ensure consistency. Also 3:1 underground and 5:1 above with feb only. Washing up liquid weakens the mix

[@freshpootube]

Rob Songer has a good explanation as to why washing up liquid is bad for the mix.

[@Walloped97]

How do you know your string line is right @ 0:20

[@ridagaceb7689]

I like to built wall by myself Thank you

[@samantafox286]

goood job. thanks

[@andrewspence5642]

Muck ? Washing up liquid ? Sorry if you use washing up liquid the detergent will break down the cement weakening the mix. 4 to1mortar mix for below ground blockwork.

[@pauldoherty8432]

Washing up liquid drawers the salts out and causes white stains, rust in the cement mixer will end up in the compo and cause stains too

[@temitoperaheem7262]

How many inches is in between the blocks how many inches book

[@kojomensah7474]

If you are in a hot climate and you are using cavity wall will the air in the middle keep the inside cool pls ??

[@HomebuildingMagazine]

Any viewers in a warmer climate than the UK want to answer this?

[@jamietalbot7254]

Washing up liquid greatly reduces the setting strength

[@charleschasakara5024]

Hello do you know any bricklayers how are taking on apprentices

[@jefflosey1561]

For us Americans...? Washing up?

[@jamietalbot7254]

@MAGNI 🤣🤣🤣

[@paulconway384]

I had a wall built in 1982 and the chap used loads of fairy liquid. Still as good today.

[@mourachinha44]

What’s the reason for not filling the gap with 100mm insulation or not having the air gap either side? Thanks.

[@HomebuildingMagazine]

The air gap helps keep the air dry, and prevents moisture. It also reduces cold-bridging.

[@samuelellwood3643]

Band of builders👍🏻👍🏻👍🏻👍🏻

[@williammarshall2175]

Nnn

[@tomjones1139]

what if i lay my first course of block flat then build my wall would that be ok

[@SimonSideburns]

It won't be 300 wide (100 for first block, 100 cavity and 100 for second block) as blocks are only usually 215 tall.

[@markcup1]

Band of builders 😍👌

[@PeterParker-hf8ok]

is it normal in the uk not to place steel bar for reinforcement inside your blocks?

[@HomebuildingMagazine]

It depends on the size / type of build involved. We'll often use steel rebars for full builds and some larger extensions, but it's a case-by-case basis. This built didn't require it according to the building regulations.

[@PeterParker-hf8ok]

@@HomebuildingMagazine cool . we have earthquakes every now and then in hawaii hence i wondered. Thank you!

[@DeusEversor]

5cm insulation in 10cm cavity? whats the rest of it gonna be? Also, will the insulation forward any sideways pressure between two skins? because i have a feeling that both brick layers alone are kinda thin and if they could move independently, then some force could easily tumble one or both layers

[@HomebuildingMagazine]

5cm insulation, and 5cm air. The insulation gap prevents moisture build up, and condensation.

[@DeusEversor]

@@HomebuildingMagazine oh, thanks :)

[@stevens5541]

So many experts in the comments section.

[@HomebuildingMagazine]

We know... ;-)

[@williamwhitmore1]

Could you please explain why only 50mm cavity wall insulation, why not 100mm to completely fill the gap ?

[@ashyclaret]

You need the gap,in-case of was water bridging from the outer leaf.

[@0000crusader]

You can have full fill insulation but it is best to least at least a 25mm gap to allow air to circulate within the cavity. This will help reduce interstitial condensation within the wall and stop any penetrating moisture for the external leaf tranferingvto the inner leaf.

[@jeffreyloftus3617]

There has to be a "breathing" space

[@martinjeffery3590]

To allow the wall to breath and stop the transference of moisture from 1 skin to another

[@JayKTS]

Why would you fill the cavity completely with insulation as it will get wet with heavy rainfall ,,, so what you got is wet insulation 🤷🏻‍♂️🤷🏻‍♂️

[@SOMALIHOMEIMPROVEMENTS]

Where in the country are you guys based i wouldnt mind working with you lads for free on the weekends to up my skills lol

[@kenboon1478]

What's happened to the lads fingers ? Chopped them off with the bolster

[@cannywf1]

How deep was the concrete footing?

[@HomebuildingMagazine]

For this build the concrete footing went down approx 1metre. (I think we covered this in video 2). Cheers!

[@kellylouise6723]

What happens if those bricks aren't straight with the house, can it be rectified without taking it down again?

[@kellylouise6723]

Can the walls be put straight?

[@kellylouise6723]

Also, how to do you string line on a semi detached house party wall? Thanks.

[@HomebuildingMagazine]

Hi Kelly, if your brick wall isn't straight, there isn't much you can do about it once the mortar has set. How catastrophic is it? It depends how wonky they are, and what the wall is designed to do / support etc. It might not be the end of the world depending on what the purpose of the wall is, and you could possibly disguise the imperfections with cladding ... but without knowing too much about it, we'd suggest spending time getting the wall straight first, instead of time spent trying to hide it! :)

[@daddyosixwhoo6898]

I am going to build a wall like this and build a timber suspended floor and timber frame to give me an extra room off my front room with patio doors, I gather I will need to put air vents in the brick wall and would I need planning permission, it will be 5 meters in length and 3 meters in width, roughly 2.6 meters high. Thanks

[@HomebuildingMagazine]

If it's a single storey extension at those dimensions, then you *should* be able to build it without acquiring planning permission - it should be acceptable under Permitted Development. However, check with your builder / designer / project manager before you break ground! You'll need to ensure the construction meets Building Regulations so definitely best to speak to an expert.

[@kitchensexpert8242]

Permitted development in my area only lets you erect 3m out from the rear of the property

[@joewilson6930]

can you use light block instead of concrete

[@cailanhowett5534]

Yes you can use thermalite if this is still any use to you mate

[@katiejohns3415]

how do you make sure the corner block is the same height as the house block?s

[@HomebuildingMagazine]

String lines. Builder's best friend!

[@katiejohns3415]

@@HomebuildingMagazine thanks for the reply. So you string it and then put your level on the string line?

[@HomebuildingMagazine]

Yes, exactly that. Good luck!

[@stuartandrews4344]

Why do peeps insist in using washing up liquid,it can cause efflorescence on the brickwork,plus it weakens the mortar overall strength. Use the proper mortar plasticiser.

[@HomebuildingMagazine]

Nobody suggested using washing up liquid. Andy says "in old money" e.g. something people would have done in previous years. He specifically suggests using plasticiser, or "Feb".

[@augustuspatrone6790]

Excellent

[@bobbuilder81]

It was going so well till you mentioned washing up liquid ! Massive NO !

[@patrickjay6434]

Are these thermalite blocks?

[@HomebuildingMagazine]

I believe these were standard concrete blocks, rather than thermalite.

[@patrickjay6434]

Thanks :-)

[@joedamangu1324]

how thick is your concrete footing.

[@HomebuildingMagazine]

It's 1m deep, and just over 300mm wide in accordance with building regs.

[@joedamangu1324]

@@HomebuildingMagazine thnk you how much in one meter deep is concrete mix as i saw in you video does look like 1 meter hi is concrete thak you foy your help.

[@ismaeelgitta2576]

Shouldn't you use frame ties.

[@maryellis3661]

does the cavity have to be 100mm

[@anthonymclean9743]

Yes 👍

[@petesteele4487]

First few mixes should be 3-1 It's underground so should be substructure muck. 5-1 is no good underground would not be strong enough to pass regs.

[@brownstonemasonry4305]

I use 2-1 or 3-1 but i'm in Canada. Was in Nova Scotia (hence 2-1) and now im on Vancouver Island. Pretty common to see 3-1 here. 5-1 seems pretty weak. But whatever works

[@stevejeffries1603]

DONT USE WASHING UP LIQUID But use fed thats fine

[@majorkonfuzion1007]

no need for rebar??

[@lfgeorge3]

Where is the rebar, how can he get away without rebar in the footer

[@HomebuildingMagazine]

No rebar required on this build in accordance to Building Regulations - not an essential part of the foundations for an extension of this size / shape in the UK.

[@kungfusing1]

They sure don’t make houses like this in Australia. Timber frame, a brick veneer and bingo, one overpriced shot hole complete!

[@pauldan7093]

That's how they make most new homes in the UK now. We call them rabbit hutches. Older houses from the Victorian and Edwardian era are far superior.

[@wayneblackberr4690]

Sub structure slightly drier engineering bricks don't absorb water

[@johnnyboy0069]

what about wall ties/

[@0000crusader]

Don't need wall ties below GL as there is usually a weak mix filling and binding the cavity

[@MattJay.]

People, he didn’t mean he was actually going to use washing up liquid 🤦‍♂️

[@HomebuildingMagazine]

Comment of the week.

[@comedy_timepass]

@@HomebuildingMagazine which insulation you use in between your walls

[@TheJeza123]

5:1 total rubbish. 4:1 for building 3:1 for pointing, washing up liquid breaks down the cement. Crazy !. Hammer in bolster verry easy to use and effective!

[@wolfhachmuth7731]

4 parts building sand, 1 part sharp sand, 1 cement, 1 lime and feb. Best mix imo.

[@danieldennett4525]

yes mate 3:1 below ground aways

[@SilverTrowel631]

A 5 to 1 mix is the UK industry standard, (Although sulphate resistent cement is recomeneded for work below ground.) One of the first things I was taught as a lad was never use a mortar mix stronger than the brick/block you are laying. The strength of any wall is in the brick/block, not the mortar. If there's any movement in a wall, you want the mortar to crack, not the brick/block. Washing up liquid does not break down cement but it contains solvents that can leave oily stains on the mortar beds. Plasticisers are very cheap now so there's no excuse for using washing up liquid.

[@SilverTrowel631]

@@wolfhachmuth7731 ............... You'll have fun trying to lay brick with sharp sand mate ..... And no brickie I know in the UK uses lime for standard brick/block walls anymore. Hydrated lime is a plasticer which can be replaced by 'Feb'. Although I often use it for weather struck pointing mixes because it gives a mortar a better color and smoother finish. Hydraulic lime is often used as a replacement for cement in mortars. It is mostly used when specified in restoration work or re pointing.

[@wolfhachmuth7731]

@@SilverTrowel631 i said 4 parts building sand, 1 part sharp sand. Not the whole mix in sharp. Works well, done it many times. Lime is a replacement 4 feb, i agree. But it don't hurt using both.

[@Z3n1tHL0rD]

Its Chemistry really, Bricklayers are chemists

[@jrice1091]

Why such a little piece in the corners?

[@petesteele4487]

To maintain the half bond.

[@upfrontgaming1061]

who so you get the staggered bond, with the little piece in the corner means the block on top will be half on the block underneath o get the bond

[@keysersoze3618]

100mm cut means next block laid on top of it is half bond

[@jrice1091]

I understand the piece is to maintain bond but it's the wrong size piece in my opinion and how we do things here. I was always taught that you never put anything smaller than a half in the corners unless it dictates because of an opening. We would put a larger piece in the corners it makes it stronger and honestly looks better. So for instance with the material laid in the video it appears to be a 4" wide block and going by a comment made by someone else 100mm. I would eliminate the 100mm piece turn the corner block the other way and place a 300 mm piece or a cut that is 3/4's of the total length of a full unit. To each their own but most competent inspectors or architect's here wouldn't let that pass without a very good reason. Hope that helps you fellas understand.

[@christopherwright1100]

Been in the game a long time now and never come across an architect or building inspector who questioned this method.

[@ronnierobinson1502]

You don't get paid for cutting....hammer bolster quicker than stihl saw

[@christopherwright1100]

Why are you telling people to add washing up liquid? Surely you must know the amount of air entrainment using this leads to a weaker mix.

[@patrickkelly7085]

the houses we built in the sixties with washing up liquid added to the mortar don't appear to have suffered

[@chmoduk]

I don't think he's telling you to use it, he was stating that some do use it, but anyway the plasticiser is really cheap.

[@patterdalezipsuzilil]

I thought concreate takes at least 3 days to cure?????

[@HomebuildingMagazine]

It does take that long to cure fully, but it's solid enough to begin to build on after 24 hours in decent weather conditions. Any wet weather or low temperatures will increase that time.

[@rinakumariu.m.sgambhira8351]

Indian army

[@Okhorgotekonati]

Thank you