Perhaps this is a silly question ?
The original DPC on the house is 2 layers of slate with mortar either side, resulting in a thickness of about 30mm, do you measure the 525mm from the top or bottom of this DPC thickness ?
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Perhaps this is a silly question ?
The original DPC on the house is 2 layers of slate with mortar either side, resulting in a thickness of about 30mm, do you measure the 525mm from the top or bottom of this DPC thickness ?
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Not a silly question. Are you building off the existing line of the flank or stepping the new wall in a bit. If you are using LBC Rustic metric size bricks you will find they are slightly smaller than the original.
If you are following the existing brick gauge it would probably be better to take the new brickwork slightly nearer the top as the new DPC will most likely be a thinner joint. Depends if you want a thicker joint showing to match the existing.
If you are following the existing brick gauge it would probably be better to take the new brickwork slightly nearer the top as the new DPC will most likely be a thinner joint. Depends if you want a thicker joint showing to match the existing.
And the above post is a good illustration as to why you should not be just thinking of things in isolation, but planning the job and materials as a whole. What size cavity, what gauge bricks, what thickness and type of blockwork, what type of insulation. As each can potentially have a knock-on effect to something else.
So its not just a case of how much concrete do I put in the trench I've just dug.
So its not just a case of how much concrete do I put in the trench I've just dug.
Thank you Stuart45
No i'm not going to use LBC, I'm going to use Carlton ripley rustics instead
I fully understand what you are saying Woody, but can i not ask a simple question without having to list every step and material i'm intending to use throughout the whole job ?
No i'm not going to use LBC, I'm going to use Carlton ripley rustics instead
I fully understand what you are saying Woody, but can i not ask a simple question without having to list every step and material i'm intending to use throughout the whole job ?
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That's what I'm laying on our current job! 73mm fellas. Easy brick to lay (thank goodness).
You can ask, but the point is the question is not as simple as you think it is. But you are building it, and paying for the extra or the waste, so its up to you.
BTW, you would not work to the existing DPC if the floor height is different
Glad you said that
I'll be using the 65's - had a look at them being used by a local builder, nice bricks, IMO they look a much better match than the LBC rustics/antique to those used when my house was built - living next to the kings Cross main line, My house has been subjected to a lot of weathering, soot and diesel over the years, so using a nice new LBC rustic just looks terrible.
What you find is that the metric bricks are around 2mm smaller at 65mm which does not sound a lot, but it can show in the joints if you are following the existing gauge.
Years ago it could be a bit of a problem when building extensions, especially if the existing joints were slightly bigger to start with.
Nowadays extensions tend to be set back half a brick and wall starters used, instead of toothing out and pulling the line off the existing.
Years ago it could be a bit of a problem when building extensions, especially if the existing joints were slightly bigger to start with.
Nowadays extensions tend to be set back half a brick and wall starters used, instead of toothing out and pulling the line off the existing.
I will be using wall starters, and looking at a lot of the existing joints they are measuring 8mm -10mm, a lot are 8mm so hopefully the gauge should be easier to follow. my next door neighbour has joints around 15mm looks terible
Measure 10 courses then divide by 10 (or do 20 or 30) to get a better average. Measure from top of brick to top of brick somewhere away from the DPC. As I said earlier, 10 courses on our job measures 890mm. Our damp joint is 50mm thick! However, the brick lends itself well to mucking up, so no problems there.
I finished the inner blockwork at the top of the 50mm DPC joint because that is where the floor level is.
Externally, all looks the same.
I considered keeping the bed courses independent of the exiting masonry but decided that because of joining onto an existing chunk of garage and the frontage toothing, it made more sense to stick with the existing gauge.
I finished the inner blockwork at the top of the 50mm DPC joint because that is where the floor level is.
Externally, all looks the same.
I considered keeping the bed courses independent of the exiting masonry but decided that because of joining onto an existing chunk of garage and the frontage toothing, it made more sense to stick with the existing gauge.
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My approach too - the full plans process is worth its weight in gold. I do mine over winter so that by the time February comes everything is researched and detailed in the plan, then in spring/summer I can spend maximum time on the shovel and minimal time talking to you lot
Are you sure that's not 9 courses.
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