DIY Doctor

Waterproofing a rendered block planter

Postby renfrew999 » Fri Oct 09, 2020 1:46 pm

Hi. I'm building a large rendered planter from concrete blocks and I've read that its advisable to paint the interior with tanking paint. My question is, as the soil will not be to the brim I will need to render the top 10cm or of of the interior. If I paint that section with the waterproof paint will the render adhere to the blockers or should I leave that section free of paint? Thanks in advance
renfrew999
Rank: Apprentice
Progress to next rank:
10.5%
Posts: 7
Joined: Sat Jul 04, 2020 9:19 pm


Sponsor

Simply Build It

Postby stoneyboy » Sat Oct 10, 2020 7:11 pm

Hi renfrew999
Concrete blocks are porous, if the inside is going to be painted it is impossible to fill all the fissures and stop damp from the soil entering the blocks. With the outside rendered some areas of the rendering will eventually blow by frost action. It will therefore make little difference if you paint to the top but probably better to leave the top few cm unpainted.
Regards S
stoneyboy
Rank: Project Manager
Posts: 3675
Joined: Wed Dec 10, 2008 6:44 pm


Postby renfrew999 » Sun Oct 11, 2020 9:07 am

Thanks for the reply. Having read up I think its tanking slurry that'll be using the paint the inside of the planter
renfrew999
Rank: Apprentice
Progress to next rank:
10.5%
Posts: 7
Joined: Sat Jul 04, 2020 9:19 pm


Postby stoneyboy » Sun Oct 11, 2020 1:53 pm

Hi renfrew999
If you haven't started building the walls yet it would be wise to consider using 3+ rows of engineering bricks at the base to form a DPC but leave the lowest ones un-rendered.
Regards S
stoneyboy
Rank: Project Manager
Posts: 3675
Joined: Wed Dec 10, 2008 6:44 pm


Postby renfrew999 » Sun Oct 11, 2020 5:48 pm

Nearly finished it but thanks for the advice! It may help someone in the future.
renfrew999
Rank: Apprentice
Progress to next rank:
10.5%
Posts: 7
Joined: Sat Jul 04, 2020 9:19 pm


Postby renfrew999 » Sun Oct 11, 2020 9:25 pm

Would it make more sense to line the planter with dpm as opposed to painting it with tanking slurry?
renfrew999
Rank: Apprentice
Progress to next rank:
10.5%
Posts: 7
Joined: Sat Jul 04, 2020 9:19 pm


Postby stoneyboy » Sun Oct 11, 2020 9:33 pm

Hi renfrew999
My preference would be to form a mini soakaway in the bottom and use a pond liner but pierce holes in the bottom.
Regards S
stoneyboy
Rank: Project Manager
Posts: 3675
Joined: Wed Dec 10, 2008 6:44 pm


Postby stoneyboy » Sun Oct 11, 2020 9:33 pm

Hi renfrew999
My preference would be to form a mini soakaway in the bottom and use a pond liner but pierce holes in the bottom for drainage.
Regards S
stoneyboy
Rank: Project Manager
Posts: 3675
Joined: Wed Dec 10, 2008 6:44 pm



Display posts from previous
Sort by
Order by



  • DIY How to Project Guides
  • DIY how to tutorial projects and guides - Did you know we have a DIY Projects section? Well, if no, then we certainly do! Within this area of our site have literally hundreds of how-to guides and tutorials that cover a huge range of home improvement tasks. Each page also comes with pictures and a video to make completing those jobs even easier!


 
  • Related Topics