What is a BRE 365 soakage test?

If Preston City Council, Chorley Council, South Ribble or building control have asked for a BRE 365 soakage test before they will accept a soakaway, they want measured evidence that water will soak into your ground.

BRE Digest 365 is the method UK councils commonly recognise for soakaway soakage tests. In practice we dig a trial pit at the depth your soakaway would sit (up to 1.8 m), fill it with water from your outside tap three times, time how the level falls, and write up the soakage rate for each fill plus a design soakage rate.

You may also hear it called a soakage test, soakaway test, infiltration test or percolation test. For surface-water soakaways, BRE 365 is the usual method. That is different from a foul septic “perc” test under Building Regulations Part H / BS 6297.

What you get

Acorn carries out the dig and the test with our crew — our micro digger fits through gates as narrow as 75 cm — then sends a branded Acorn PDF made from our report template. The report includes the pit log, photos, readings, soakage rate per fill and design soakage rate. Your report within 5 working days of the test, often sooner.

We do not size the soakaway, design the drainage, or issue engineer sign-off or a competent person certificate as part of this service.

Cost in brief

From £850 + VAT for a standard one-pit test about 1.2 m deep. Most finish in a day. Slow ground such as clay may need a second day at £400 + VAT (so the most for that standard one-pit package is £1,250 + VAT). Deeper pits 1.2–1.8 m from £150 + VAT extra; deeper than 1.8 m by quote only.

Next step

Enquire about a BRE 365 soakage / soakaway / percolation test in Preston