Bespoke window treatment

Lots of architects specify bespoke oak windows and doors to be left untreated, so that they age to a lovely grey colour. This is all well and good…but manufacturers will not warranty their goods to the end user unless they have been treated with their own particular treatment system. The reason for this is quite simple… the manufacturer is covered by the supplier of their treatment system. If something does go wrong and the units were treated to the supplier’s specification, then they will cover the cost of any replacement.
The argument that you will be treating the units yourself later will not alter their attitude, as their treatment system will be applied during the production process and will cover things like the internal faces of the mortice and tennon joints, which cannot be treated retrospectively.
There is a solution to this, but it needs to be dealt with at an early stage in the negotiations. A product called Sioo Wood Impregnation Solution is available which leaves the oak fenestration  as if it had been aged for a couple of years…but in about four weeks. At the same time, it is impregnating the timber with silica crystals protecting it for up to ten years if applied correctly.  It is a two stage system with stage two being repeated after 6 – 14 months to achieve full protection for up 10 years.  There is a very scary period of time when your oak will turn a bright orange colour, but this is short lived and very soon the oak will take on its natural silver grey colour.
If you can negotiate terms with your bespoke fenestration supplier to treat his products with this treatment, instead of his usual product, and provide you with a modified warranty then this should suffice.  I have written to Silva asking if they would consider providing warranty cover to a bespoke joinery manufacturer in this scenario and I will add their reply to a future blog post.
Stay happy and keep pushing on, Self Builders.

Project Management

What is this and why should we use it for our building project?
Read more


What should we look for?
Can we afford to do this?
Read more


Finding out what it should all cost.
Keeping those costs under control.
Read more


How it can really help a project.
How to do it properly.
Read more

Tender Process

Making sure the build team is properly chosen and prepared.
Read more


Finding the best value materials.
Making sure they stay that way.
Read more

Site Management

Working with the whole team,
helping everyone to get it right.
Read more

CDM 2015 Regulations

Carrying out the Principle Contractor Role For CDM 2015 Regulations
Read more