Do I have to paint a sand cement render

Hi Sarah, I would suggest you pour a glass of water over the render to determine whether the render contains an integral waterproofer . If the water beads up and runs down the wall it will ok to leave the render as it is. ( although most integral waterproofers are only good for around 10 years ). It would need to have a permeable clear sealer applied after this anyway. If the test water soaks in straight away then you need to apply a permeable clear sealer ASAP to stop rain water damaging the render. Raw render will attract dirt, algae, and mould in no time at all, and unfortunately the first bad cold spell will start the freeze thaw process and blow the render.In the old days ( showing my age here ) we would trowel the render off closing the pores making it impervious to rain water, today it seems most render is just sponged off leaving the pores open which is ok if its going to be painted.

You can leave it without paint the render should have been mixed with a waterproof mix agent and will still protect you house, however if your wall is not matching to rest of the street the council coukd ask you to paint to match. All the best Christopher Hepworth

By sealing the render you will improve the lifespan of the finish. A clear water seal such as Thompson’s or the Sandtex equivalent is ideal and both offer warranties. Application does not require a high level of skill and can be carried out by a keen DIY er.

Yes you can leave it as it is but will need to be sealed with a masonry sealer.

Perfectly ok to leave it just the way it is.

Yeah you can seal it with exterior sealant to protect it from weather corrosion