Timber Sole Plate Height Above Ground

150 mm

The lowest timber elements of a building, such as sole plates, should be positioned a minimum of 150mm above the finished ground level

Every figure for this topic is on one page: Timber frame stud spacing, sheathing and restraint straps

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The lowest timber elements of a building, such as sole plates, should be positioned a minimum of 150mm above the finished ground level. This height can be reduced to 75mm in situations where the site does not have a high water table and the cavity is not susceptible to standing water.

Basis in regulation

Part C
Approved Document C
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How to check it on site

Measure the distance from the lowest timber element to the finished ground level to ensure compliance with the minimum height requirements.

Common failure

Timber sole plates installed too close to ground level increase the risk of moisture ingress and timber decay.

Last updated 23 August 2026. This is our editorial summary of publicly available regulation, not building control approval or a warranty determination.

Related dimensions at this stage

Minimum

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Minimum

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150 mm

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450 mm

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Maximum

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110 mm

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DPC and Cavity Tray Locations

150 mm

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