Good Morning,
I was hoping for some advise if you wouldn't mind.
I am building a workshop/garage, at the moment it is single skin blockwork with a warm roof and screed floor. I have screwed in treated timber battens into the wall and plan on installing sheep's wool insulation between. I have not put a plastic membrane behind the battens because I want the building to breath (there is a vapour barrier in the roof and a DPM under the floor insulation).
So now I need to think about the external render. I have had a plasterer do some internal work a year ago (house) which I was pretty happy with and was hoping to get him to do the job. He has given me the choice of K-Rend or Sand/Cement/Lime. Without trying to open up a can of worms, my current thinking is sand cement as from what I have read, it is easier to repair when cracked, can be repainted, and the K-Rend seems harder to keep clean because of the texture.
The chap has told me that he will not be putting a mesh up with the sand/cement, and is not willing to put in a waterproofing additive because "It might cause sores on the wall" (the office manager is not a native English speaker - I'm not quite sure what is meant by this). They say that a Silicone masonry paint will be sufficient for damp proofing.
Would anyone mind giving a professional opinion on this? Will Sand/Cement/Lime with Silicone paint be sufficient? Or should I be insisting on an additive? How long could I expect such a render coat such as this to last before cracking (I have been told anything from 8 years to 20!). When the cracks come, are they going to be repairable to the point of being weathertight, without a complete re-render?
At the end of the day it is a single skin workshop, and I am prepared for regular ongoing maintenance, painting etc - but still want to be as dry as reasonably possible.
Thanks for any advice.
Richard
I was hoping for some advise if you wouldn't mind.
I am building a workshop/garage, at the moment it is single skin blockwork with a warm roof and screed floor. I have screwed in treated timber battens into the wall and plan on installing sheep's wool insulation between. I have not put a plastic membrane behind the battens because I want the building to breath (there is a vapour barrier in the roof and a DPM under the floor insulation).
So now I need to think about the external render. I have had a plasterer do some internal work a year ago (house) which I was pretty happy with and was hoping to get him to do the job. He has given me the choice of K-Rend or Sand/Cement/Lime. Without trying to open up a can of worms, my current thinking is sand cement as from what I have read, it is easier to repair when cracked, can be repainted, and the K-Rend seems harder to keep clean because of the texture.
The chap has told me that he will not be putting a mesh up with the sand/cement, and is not willing to put in a waterproofing additive because "It might cause sores on the wall" (the office manager is not a native English speaker - I'm not quite sure what is meant by this). They say that a Silicone masonry paint will be sufficient for damp proofing.
Would anyone mind giving a professional opinion on this? Will Sand/Cement/Lime with Silicone paint be sufficient? Or should I be insisting on an additive? How long could I expect such a render coat such as this to last before cracking (I have been told anything from 8 years to 20!). When the cracks come, are they going to be repairable to the point of being weathertight, without a complete re-render?
At the end of the day it is a single skin workshop, and I am prepared for regular ongoing maintenance, painting etc - but still want to be as dry as reasonably possible.
Thanks for any advice.
Richard
