Timber Strength Grading to BS5756,

for existing in-situ timbers & new timbers pre-installation.


We do this

In-depth evaluations assessing the strength of timber

Which does this

Establishes if existing timbers meet performance requirements


Giving you this

Classification status - the data needed to inform your project

In-situ visual strength grading of temperate hardwoods

(to BS5756)

If you are a designer or engineer, you’ll need to be confident that new or retained structural timbers will perform as envisaged under working loads and stresses: a proposed change of use for an old or historic building could place greater loadings and stresses on those structural timbers.
In-situ visual strength grading is a method of determining the potential load bearing capacity of timber components, and will help determine if timbers are suitable to take the projected loading, or if they will require strengthening works.

The performance of a structural timber component is determined by its species, its dimensions, moisture content and its natural growth characteristics.
It is those growth characteristics such as knots, slope of grain, fissures, insect and fungal defects that are assessed by visual strength grading, and will determine the indicative strength classification assigned to each timber component.

Wondering if existing timbers meet performance requirements for change of use?

... let us take out the guess work & give you the data & confidence to move forwards

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