If you are looking at converting or refurbishing an existing building, you may come across challenges when it comes to preserving the existing timber.
It is often only a small, but structurally critical section of timber that has become rotten, infested or broken and if not repaired correctly could spoil the architecture, or worse, devalue the property.
As timber is an extremely valuable resource and is considered important to conserve as much of the original material as possible, repairs to historic timbers can be tricky. So what can be done to replace or repair the defective section and allow the majority of the timber to be retained?
Repairing timber defects in existing buildings
Repairs can be carried out so that the structural capacity is maintained and wastage of timber is kept to a minimum.
Resin repair systems can be used to remediate a wide range of timber defects, including decayed truss or beam ends, structural cracks, either natural or induced.
In the majority of repairs, the basic components used can be categorised as:
a) The parent timber
b) The replacement timber
c) The reinforcing or connecting materials
d) The epoxy resins
The epoxy resins used are suitable to act as both a replacement material to substitute the lost timber and as an adhesive to bond on re-claimed timber of a similar age and appearance.
Recommendations when dealing with timber resin repairs
- Timber resin repairs should only be undertaken by specialist companies.
- In accordance with Chapter 2 of our Technical Manual and Regulation 7 of the Building Regulations 2010 in England and Wales, all materials used must be suitable and shall be used so as to fulfil their purpose.
- In the case of roofs, the specialist company should demonstrate compliance with Chapter 7 of our Technical Manual and Requirement A1 of the Building Regulations 2010.
- Resin repairs should be designed by an independent Chartered Structural Engineer who is confident of the specified product’s structural integrity and former proven use.
- The Structural Engineer should also monitor the remediation process and confirm that the completed repair has complied with their design and specification.
Whilst early resin systems were met with scepticism from some heritage bodies with concerns regarding its durability, today’s resins and timber resin splice systems are now widely accepted as a viable means of timber preservation and have many beneficial properties, including:
- High versatility
- Long shelf-life
- Low fire risk
- Low odour
- Wide useable temperature range
- Low cure shrinkage
- Excellent adhesion and toughness
Property Care Association: www.property-care.org
By Frzana Ferguson
Please Note: Every care was taken to ensure the information in this article was correct at the time of publication. Any written 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. However, for the most up to date LABC Warranty technical guidance please refer to your Risk Management Surveyor and the latest version of the LABC Warranty technical manual.