Painting With Minimal or No Sanding
I'm currently painting the inside of my house. The walls currently are painted with a semi-gloss finish, which has been on them for around 20 years. I have used TSP to clean the walls. Is there a way I can paint over the old finish without having to sand the walls?
K in Scranton, PA
Sanding can be avoided in two ways. First, you can use a heavy duty primer sealer as a first coat before applying your finish paint. The oil based products, such as Kilz and Zinsser Cover Stain, will stick to anything (even glass), and give a good stable surface for top coating.
If you prefer not to use a primer, you can use a deglossing liquid such as Wilbond. The deglosser cleans and prepares the surface for repainting. If the original paint was latex, deglossers make its surface slightly tacky. If the original paint was oil, the deglossers are less effective... a light sanding to scuff up the surface might be desirable before using the deglosser, or instead of it.
If you want the best of both worlds, use the deglosser immediately prior to priming... the deglosser will remove any remaining oils or grease that the TSP missed, and prep the walls for the best possible adhesion of the primer.