Extending period properties

[Gareth Hughes]

When it comes to the brickwork on the extension, is there any advantage to using reclaimed bricks over a new 'heritage' brick?
Thank you.
Matt

There are no advantages.
1. reclaims almost always produce a terrible spotty effect that bears no resemblance to historic brickwork
2. reclaims encourage the demolition of old buildings (and theft of materials)
3. reclaims discourage the continuation of the craft of brickmaking

 

[plasticpigeon]

I wish I had used new quarries, not reclaims in my kitchen for the reasons Gareth states.

 

[Feltwell]

I wish I had used new quarries, not reclaims in my kitchen for the reasons Gareth states.

The new quarries I've seen are far too perfect - uniform size, thickness, colour and texture. The original Victorian ones vary a lot more, not to mention they're normally partially pitted on the top surface and wear slightly unevenly, I'm guessing because of variation in the clay used and over 100 years of slightly damp floors!

I've original quarries in my kitchen and reclaimed ones in the adjoining scullery. The scullery ones were badly laid by a previous owner - they're much more uneven than the original ones in the kitchen, due I think to variable thickness tiles being laid over a uniform screed of adhesive, rather than the time being taken to bed each tile individually to get an even floor. But they still look better than new ones would I think - New ones would look as out of place as shiny white UPVC windows do.

Pamments - there's a different story, there are some nice new ones being made.

 

[Craig89]

I have to agree with Feltwell....the problem with new materials is that they are just too perfect. With my extension, the reclaimed bricks I used to match the commons are not the best match in terms of colour or texture (they are pressed as opposed to wirecut) however because of their age there is a big variation in size, shape and features (burn marks etc) and this make them blend in much better.

I colour matched cement mortar to lime mortar. My lime mortar was grey in colour due to the ash that was mixed in the mortar. I used an Everbuild black oxide powder dye and after carrying out some samples managed to get a near perfect colour match. For white you probably want white cement and probably a lighter sand to begin with.

 

[overlander matt]

That's good to know about the white mortar - we will have a play with this in the coming weeks to get the right blend to match the lime mortar elsewhere. I had originally only considered reclaimed bricks but I did see a couple of packs of bricks from Imperial Bricks at a reclamation yard last week that has me thinking again. There is certainly variation in the size and texture...

I previously mentioned the house not showing any signs of damp. I have however found some unusual measures taken to prevent ingress of moisture from outside I the form of a polythene sheet in a chipboard clad wall. The floor has also been covered in bitumen. I do wonder what I have to do to put all of this right... it probably goes without saying that it all needs to be stripped out.

Thanks for the helpful input on this.

Matt

 

[88v8]

That's good to know about the white mortar - we will have a play with this in the coming weeks to get the right blend to match the lime mortar elsewhere. I had originally only considered reclaimed bricks but I did see a couple of packs of bricks from Imperial Bricks at a reclamation yard last week that has me thinking again. There is certainly variation in the size and texture...

I previously mentioned the house not showing any signs of damp. I have however found some unusual measures taken to prevent ingress of moisture from outside I the form of a polythene sheet in a chipboard clad wall. The floor has also been covered in bitumen. I do wonder what I have to do to put all of this right... it probably goes without saying that it all needs to be stripped out.

Agree that new quarries are an eyesore.

We used new bricks on an extension in our previous house. Oddly enough, the house had been built with reclaims as the builder back in 1921 had no money, so he told us when we bought the place in 1980. Problem with the new bricks was that we had only seen a sample, and when they arrived in bulk most of them looked nothing like.
Fortunately the original house and all but one new flank wall was pebbledashed so in the event it didn't really matter.

Can one get new imperial bricks? No good trying to bond metric to imperial, it will look a mess.

As regards the past efforts at fending off damp, you can bet it was done for a reason. The easiest solution for a solid floor is likely to be limecrete with a breathable topping of stone or quarry. This may also remove the damp problem in the walls as the moisture will no longer be going sideways.
Not to say the damp vanishes of course. It percolates into the house and then needs to be ventilated out via open chimneys.

In this case I revise my previous observations on other Overlander threads that lime plaster serves no purpose in a dry house, given that the house probably was not dry.
In a house with the normal level of 'period' humidity, lime acts as a moisture buffer and along with breathable paints will help avoid condensation and mould.

Ivor

 

[Craig89]

"Imperial Bricks" the company are near me and I have been there, they do sell a nice sellection of bricks in imperial sizes. I was under the illusion that they were made there, they are not, they are imported from India I believe. I would also doubt that there are much variations in size, the 50 I brought were certainly all the same, but that could be a good thing depending on your view.

 

[overlander matt]

The extension build is now well underway and we will be out of the ground by the end of the week. We changed the design slightly, removing the two windows and increasing the size of the left hand bifold to improve symmetry. I had thought this would have caused a delay with the council needing to consider the changes but it seems they have other things to worry about and they have no objections. Hoorah! That means I now need to make some progress making decisions about the cement and brickwork.

I am keen to use a white cement mixture to closely match the lime used on the pointing elsewhere. The natural sand colours in the area are red and a pale yellow. Using a white cement (Blue Circle's Snowcrete) and the yellow sand only resulted in a pale yellow finish which is not acceptable. I guess that means we are going to need to find a white sand. Does anyone have any experience sourcing white sand? The Buildbase website 25kg bags but are not stocked locally. I also noticed Blue Circle suggest adding hydrated lime to the mix for certain applications. Presumably this would also whiten the mix but probably not enough for our needs.

We found a good reclaimed brick from elsewhere in the county that matches one section of the existing house pretty well. With the right colour cement, and brickwork detail, I hope the extension will complement the original building better than the current mish mash of windows, doors, cement pointing and other details. One idea I would like to try, following on from the earlier discussion on soldier courses above the bifold doors, is to use rubbed arches across the 3m openings. This gives a nod to the detail on the front of the house. I have found a couple of companies who make the voussoirs/tapered bricks for these arches. Has anyone any experience building such arches? I'm keen that these are built from the bricks being used on the extension if possible. The arches will be purely decorative as we'll still be fitting lintels.

Any thoughts on this one much appreciated. On a slightly different note, on excavating for the footings, I found the subterranean brickwork of one section of the house we will build the extension onto was covered in a 6" layer of clay. Was this common practice to encase footings in clay? At the other end of the footings there was no clay...

 

[TheForge]

Hi Matt,

Good news on the extension. My two penneth worth would be that if you want the extension to match the lime pointing elsewhere why not build the brickwork with an NHL lime mix?

Presumably the extension is a blockwork inner skin laid in cement and the brickwork a secondary skin tied to this?

Although the new brickwork will have a DPC, if it’s made of reclaimed, or soft handmade bricks, cement bedding mortar will have the same detrimental effects on the bricks that it would in an older wall during phases of freeze thaw as moisture will more readily track through the brick and potentially spall the faces.

You can always lighten a mortar by substituting chalk or a light stone dust (Portland or Bath stone for example) for a proportion of the aggregate. However finer aggregates will encourage greater shrinkage. It’s the fines in the aggregate that have the greatest colouring effect on a mix and a well washed sand should have less colouring effect.

There are light coloured sands available but you’ll need to speak to a specialist supplier rather than a local builders merchant to ensure a consistent washed sand.

Something like 1 part NHL, 2 parts washed quartz sand, 0.5 part stone dust might get you close in colour.

 

[overlander matt]

Thanks Forge. Until I read your post, I was convinced that the white cement mortar was the way to go. The poor availability of white sand makes me more doubtful. Your argument for using lime sounds reasonable. It would certainly be good to get a perfect match with the other lime and brickwork. Are there any drawbacks to the NHL lime used in this way ie tied to a blockwork inner leaf? Although temperatures are still fairly mild for this time of year, they are not ideal for lime work.

Thanks in advance for any suggestions.

 

[TheForge]

The only real drawback is how well the wall ties are held by the lime mortar, you would need to use more ties at smaller intervals than with a cement mix.

Ceramic ties could be used instead of steel to reduce risk of corrosion.

The number of courses that can be laid in a day will likely be less than cement, depending upon how dry a mix the bricklayers can work with.

 

[88v8]

I think all wall ties are stainless nowadays, so the corrosion problem has vanished. Hooray!

As colour is often critical with lime, a lime supplier would be a good source of sands. Even if you don't actually use lime, a suitable sand with your white cement may provide an easy solution.

Arches, jolly good. They are built off wood formwork. Often one sees them built in a different brick from the rest of the wall, so you could buy in your voussoirs even though they don't match your bricks.

Ivor

 

[lizziecupcakes]

Hi @overlander matt , I came across this thread whilst searching for topics on extending period properties. I have a 1907 edwardian house woth suspended floors. Does your houss have suspended floors and if so, did you extend a room/part of the house with suspended floors? How were the new floors built? I want a side return and/or wrap around kitchen extension. My kitchen has suspended floors, but I have no idea how the extension would be built.

Thank you for your insights

 

[overlander matt]

Hi Lizziecupcakes. In our case the house had a mix of suspended timber at the front and solid floors at the rear. We ended up extending to the rear so our extension was really of modern construction. With an insulated solid concrete slab floor. The old and new have got along well to date which had been an initial concern.