InSite | Through timber construction

Through timber construction

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This technical update provides additional guidance relating to the use of through timber construction. It is important that all workmanship carried out during construction is completed in accordance with the relevant tolerances, so that the required finishes are achieved.


Through timber construction: under this description we also include half-timber work, heavy timber framing, post and beam, oak framed and green oak framed.


From a warranty perspective we do not accept timber construction of this nature where the structural frame forms part of the external envelope.


The description in this article, for these types of construction, represents our warranty definition for this type of construction. There may be other descriptions used within the industry.


The purpose of this article is to highlight that from a warranty perspective, these represent an enhanced risk of water ingress, shrinkage, etc. Therefore, we do not offer cover for buildings constructed in this manner, regardless of the species of timber chosen to form this this type of structure.


Technical Manual guidance


We are aware that the guidance in our Technical Manual specifically discusses oak, as shown below in the extract from Section 6:


‘Green oak, air dried (seasoned)/kin dried oak is not acceptable in the external wall construction, frame, window/door construction, internal wall or roof constructions, regardless of whether it forms part of the weather proof envelope or not. Projects incorporating such oak will not be acceptable for warranty cover except where described in ‘Appendix C – Materials, Products, and Building Systems’ of this Manual.’


However, it is also considered that any species of timber used in this form of construction will also not offer a standard insurance risk for latent defects cover, despite any assurances provided.


Where a scheme of this nature is proposed to be registered to ourselves for warranty, or the construction details changed to this form post commencement, contact with our warranty surveyors must be made as soon as possible.


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Every care was taken to ensure the information in this article was correct at the time of publication. Guidance provided does not replace the reader’s professional judgement and any construction project should comply with the relevant Building Regulations or applicable technical standards. For the most up to date Premier Guarantee technical guidance please refer to your Risk Management Surveyor and the latest version of the Premier Guarantee Technical Manual.

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