Hi good evening all im wondering if anybody could advise if this pointing will hold up this winter just purchased the house and pointing seems very Sandy I’m worried incase the rain absorbs through to the inside above windows as they are just soldier course so guessing no trays etc in above. House is cavity wall with white fibre type insulation thanks
Repointing advice
- Thread starter Willy87
- Start date
Sponsored Links
It will hold up for the next 50 winters in structural terms.
However it its sandy, it will let more water. Whilst it may be a cavity so any moisture may not reach the internal room, moisture lowers the performance of the wall insulation and increases the risk of bricks shaling from frost (although from the photo they seem fine and may not be susceptible)
But that wall has been like that for years, so there is no reason to suspect there will be sudden problems if none exist now. Put it on the medium/long term to-do list.
However it its sandy, it will let more water. Whilst it may be a cavity so any moisture may not reach the internal room, moisture lowers the performance of the wall insulation and increases the risk of bricks shaling from frost (although from the photo they seem fine and may not be susceptible)
But that wall has been like that for years, so there is no reason to suspect there will be sudden problems if none exist now. Put it on the medium/long term to-do list.
Sponsored Links
- Joined
- 20 Feb 2022
- Messages
- 3
- Reaction score
- 0
- Country
I disagree with the above, the mortar is lime and has reached it's end of life it is sandy and brushes out easily.
If you didn't have cavity wall insulation (CWI) you could delay a little longer but utlimately it needs doing and you want to avoid the CWI getting wet at all costs as this will lead to internal damp and the CWI will need extracting once wet.
As an example: Over 90% of the damp issues we see are as a result of CWI issues so I would prioritise wall maintenance as prevention is a lot cheaper than cure.
That said, if you are repointing in lime mortar which I would advise, it is best carried out during spring to autumn and at the time of writing, we are coming out of winter so I would recommend getting it done this summer rather than creating a larger problem by delaying the work.
If you didn't have cavity wall insulation (CWI) you could delay a little longer but utlimately it needs doing and you want to avoid the CWI getting wet at all costs as this will lead to internal damp and the CWI will need extracting once wet.
As an example: Over 90% of the damp issues we see are as a result of CWI issues so I would prioritise wall maintenance as prevention is a lot cheaper than cure.
That said, if you are repointing in lime mortar which I would advise, it is best carried out during spring to autumn and at the time of writing, we are coming out of winter so I would recommend getting it done this summer rather than creating a larger problem by delaying the work.
- Joined
- 20 Feb 2022
- Messages
- 3
- Reaction score
- 0
- Country
In that case, use cement as a replacement mortar but the advice remains the same and as mentioned in an earlier reply - sandy mortar will soak up water and allow it to penetrate onto the cavity wall insulation. So in answer to your original question, you need to do the pointing if you are going to ensure that the Cavity Wall Insulation does not get wet.
Generally, most damp problems can be avoided if the owners don't try and squeeze an extra year or two more delay before getting any maintenance work and pointing done.
Willy 87,
The house looks like a 1950's build - if so, typically, it would not have had built-in CWI.
The CWI you describe would have had to be blown in but I dont see any of the usually obvious "blow holes" in your pics? Although your pics wont enlarge?
The pointing definitely looks very sandy, and not like cement pointing.
Whenever it is that you re-point then make sure there's a rake out of 25mm.
Presumably there are no signs of water damage anywhere in the outer walls?
The house looks like a 1950's build - if so, typically, it would not have had built-in CWI.
The CWI you describe would have had to be blown in but I dont see any of the usually obvious "blow holes" in your pics? Although your pics wont enlarge?
The pointing definitely looks very sandy, and not like cement pointing.
Whenever it is that you re-point then make sure there's a rake out of 25mm.
Presumably there are no signs of water damage anywhere in the outer walls?
D
Deleted member 292770
I do.
Although some builders were still using lime mortar in the 50's, most were using a sand/lime/OPC mix.
When mortar is first rubbed up with a metal tool the cement/lime laitance comes to the surface and forms a weathertight skin. As it weathers back over the years the sand shows through, so the colour changes and it looks a bit more sandy.
When mortar is first rubbed up with a metal tool the cement/lime laitance comes to the surface and forms a weathertight skin. As it weathers back over the years the sand shows through, so the colour changes and it looks a bit more sandy.
I have a house in a sunny coastal location, and one wall faces the afternoon sun with no shade. The exposed mortar was weak and sandy in some parts, which I think was due to drying out too fast when the wall was built on hot sunny days. The other walls did not have these patches.
DIYnot Local
Staff member
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local
Sponsored Links
