Now that the frame has been erected and the SIPs wrap attached creating a watertight shell, the oak can be cleaned. Peter has several choices on how to deal with the various discolorations that have affected the oak frame on it’s journey from tree, through the milling process at the sawmill, in the workshop and finally during the raising itself.
There are water staining marks, pencil marks, ink lines, and black blemishes where the natural tannins within the green oak have reacted with metal saw blades, not to mention muddy size nine footprints all over the frame. Peter could leave things as they are (yes, some people prefer the natural look, footprints and all), have the frame chemically cleaned using oxalic acid (derived from the rhubarb plant of all things), or sandblast the frame with fine grit.
Sandblasting it is for Peter, and a local contractor takes two days to clean off all the marks, leaving the oak frame an attractive uniform pale natural colour which needs no further treatment. It’s a messy job, unbelievably noisy and best left to the professionals. There is of course a mountain of silicone based grit to sweep up and a fair chance residual waste will turn up for a few years to come. Care has to be taken to ensure that the right grit is used, as sand that has any traces of ferrous metals will literally turn the frame black!
The first floor joists have also been installed — metal web posi joists that are light weight, super strong and allow easy access for services.
About the author:
Rob Dawson built a stunning oak frame home in 2009 for less than £100,000. He is now the owner and founder of Castle Ring Oak Frame.