Oak Frame Construction and Repair
We conserve and restore timber framed buildings all over the country. Oak framed buildings can date back 500 years, and are one of the most enduring forms of building structure. Oak framed buildings are suffering terrible decline at the moment - See below for a list of common problems.
This is a lovely 17th Century building conserved and restored in December 2008, near Telford, Shropshire. You can see clearly the cement filling large rotted holes in the timber frame, and silicone mastic running around the panels to seal the water against the wood - encouraging more rotting to the oak frame. A week later, and it has started to look the part again. Note the large tie beam at the bottom of the photo which was completely replaced. The panels were partly original wattle and daub, some lime, but mostly cement daubed over everything, and causing dreadful rot.
Timber Frame Problems - The art of Conservation and Restoration of oak framed buildings
- The use of tar / pitch to seal and 'preserve' oak framed buildings - it traps moisture into the wood, and allows rot to take place
- The use of modern paints - from late Victorian times, there has been a decorative 'fad' to paint oak frames black - it is not how they were intended to be. Modern paints trap moisture into the timber and allow rot to take place - conservation and restoration of timber frames involves removal of paints to allow the timber to breathe and dry out
- The (very common) use of cement or putty to fill holes and cracks in the timber, especially where joints have eroded over time - water is trapped against the timber and it rots rapidly
- The use of modern sealants - silicone, acrylic caulk, mastic, foam, putty etc around the infill panels - these materials seal water against the timber and cause catastrophic rotting very quickly
- The use of brick infill panels - as the original wattle and daub, or lath and lime plaster panels deteriorate and fall out, they have been replaced by brick - often using cement mortar. These have catastropic results - increased weight on the frame causes distortion, and can lead to collapse. Brick and cement hold moisture which causes rot of the timber frame
- The use of cement render on the panels - even daub panels are commonly cement rendered - this traps water into the panel and causes catastrophic rot of the timber frame members. Conservation and restoration of infill panels often involves removal of cement render and careful caulking around the edge of the panel before conserving with lime mortar and re-rendering the panel in lime render
The use of modern paints on infill panels - we often see daub panels painted with white acrylic or even worse, gloss white paint - this traps moisture into the panel and causes rot of the staves, withies and oak surrounding the panel.
- The commonplace use of galvanised mesh under supposedly lime rendered finishes on panels - often only cement with a shovelful of builders lime - lime reacts with the galvanising in the mesh and the render cracks and falls off. Conservation work usually involves removal of all of these materials and replacement with traditional materials such as lime render - but alternative meshes can be used - for instance fibreglass.