What Is BRE365 Testing?

by | Dec 22, 2020

We’ve talked in posts before about the many benefits of having BRE365 soakaways installed. They’re cost-effective, relatively easy to install and practical means of improving drainage – particularly in areas prone to flooding. Now we’re in the midst of winter, it’s the ideal time to get one placed into your garden.

You can’t just go ahead and have one installed, however, without carrying out the necessary checks and tests, beforehand. The team here at Borehole Solutions, who are experienced soakaway installers, wanted to look at percolation testing. This testing is vital for the installation of any soakaway; we wanted to look at one testing standard, in particular, BRE Digest 365.


Percolation Test

Percolation tests (also known as perc tests) help determine whether ground conditions are suitable for soakaway installation, or not. The test itself shows the water absorption rate of the soil being examined. At its simplest, it indicates how quickly water seeps down through the soil.


BRE Digest 365 

Back in 1991, the Building Research Establishment (BRE) published its guidance on soakaway design. The BRE acts as a centre of building science and as a consultancy on all things to do with the built environment. In other words, when they publish something, it’s worth following.

There isn’t just advice on soakaway construction within the Digest, however, it also contains information on calculating soil infiltration (percolation) rates as well. That’s where BRE 365 testing comes from. To meet these standards, soakaways must be able to show that water stored within it drains quickly enough so that it can still provide the necessary run-off support for subsequent torrential rainfall. According to the Digest, soakaways should discharge from full to half-volume within 24 hours.


BRE 365 Testing

To test to BRE365 involves the following:

  • First, a trial pit is excavated. This pit acts as a sortof replica of the intended soakaway. These trial pits can be dug by hand, but tend to be excavated by mini-diggers (CAT or JCB).
  • This pit is then filled with water repeatedly, and in a short space of time. Whilst this is being done, the rate of percolation is being measured.
  • These calculations can then be used to help determine the size of the soakaway required.


How Long Do Soakaways Last?

Provided that BRE 365 testing has been carried out, and its criteria has been met with satisfaction, a soakaway can be installed. Fortunately, once it’s been installed, it’s going to last you; most soakaways (so long as they’re installed correctly) will last for at least a century. Although they don’t require any active maintenance, either, it’s always worth giving them a quick check every few months just to make sure it’s all ok.


Contact Borehole Solutions For Soakaway Services

We offer comprehensive percolation testing, here at Borehole Solutions, as well as a variety of other geotechnical testing services – including WAC testing and asbestos removal. If you’d like to find out more about our BRE365 testing and soakaway installation services, then get in touch! Contact Borehole Solutions 01733 200 501 or by emailing us at info@boreholesolutions.com. Why not head over to our Instagram to check out some of our previous work?