Skeletank Solutions for Infiltration with Pervious Surfacings

Pervious surfacings are preferred, according to The Building Regulations 2000 H3, where it is not possible for impervious surfaces to be ‘freedraining’ i.e. for paths, driveways or other narrow areas of paving to drain to, ‘pervious areas such as grassland’.
In many cases it will be possible to use pervious surfacings in conjunction with infiltration within 5m of building foundations, (although ground conditions should be thoroughly investigated to ensure their suitability for this).

View the fact sheet USING SUDS CLOSE TO BUILDINGS.

Pervious Pavement Design Incorporating Skeletank HPDC Units

Skeletank HPDC Units provide designers with an ideal solution for diffusing rainwater into and out of the permeable aggregate layers* below pervious surfacings. They are available in two modular sizes (see below).

Skeletank HPDC Units are fully compliant with the requirements of BS7533-13:2009 Annex B, ‘Typical physical properties of replacement systems (geo-cellular) units’;

SELH02003 – 708 x 708 x 150mm deep, for catchments up to 100m2
SELH02001 – 2124 x 354 x 300mm deep, for catchments up to 250m2

The aggregate layers beneath a pervious surface provide one level of treatment, which satisfies Section 2 of the optional Water Quality Criteria in Category 4 of The Code for Sustainable Homes and thus gains one additional credit (if required).

*Note: when using this technique a suitable highly voided aggregate – e.g. Aggregate Industries SudsAgg or similar – should be used.

Skeletank products shown in this example

SELH02003	SELH03002	SELH05002
SELH05003

Note: Specification options for Geotextiles are a choice of either SELH05002 HydroWMS Permatex HD 300 Geotextile or SELH05003 HydroWMS Permafilter Geotextile.

Pervious Pavement Design Using Skeletank HPDC Units to Supplement Storage Volumes

If the standard permeable aggregate layer beneath your pervious surface is not providing sufficient storage to meet volume requirements (usually due to low permeability of underlying subsoils), but increasing the depth of aggregate to provide more storage is a problem (e.g. because of high water tables, or other factors restricting excavation) then the larger of the two Skeletank HPDC Units (SELH02001) can be utilised to increase storage volumes, within the aggregate layer, without increasing excavation depths.

The aggregate layers beneath a pervious surface provide one level of treatment, which satisfies Section 2 of the optional Water Quality Criteria in Category 4 of The Code for Sustainable Homes and thus gains one additional credit (if required).

Note: when using this technique a suitable highly voided aggregate – e.g. Aggregate Industries SudsAgg or similar – should be used.

Skeletank products shown in this example

SELH02003	SELH03002	SELH02001
SELH05002	SELH05003

Note: Specification options for Geotextiles are a choice of either SELH05002 HydroWMS Permatex HD 300 Geotextile or SELH05003 HydroWMS Permafilter Geotextile.

Pervious Pavement Design Incorporating Skeletank HPDC Units Below Sub-base to Increase Performance

To increase the performance of your infiltration system Skeletank HPDC Units (SELH02001) can be arranged to provide a drainage field beneath the pervious pavement aggregate layers. Using this technique will utilise the storage within both the aggregate layers and the Skeletank HPDC Units.

The aggregate layers beneath a pervious surface provide one level of treatment, which satisfies Section 2 of the optional Water Quality Criteria in Category 4 of The Code for Sustainable Homes and thus gains one additional credit (if required).

Note: when using this technique a suitable highly voided aggregate – e.g. Aggregate Industries SudsAgg or similar – should be used.

Skeletank products shown in this example

SELH03002	SELH02001	SELH03003
SELH05002	SELH05003

Note: Specification options for Geotextiles are a choice of either SELH05002 HydroWMS Permatex HD 300 Geotextile or SELH05003 HydroWMS Permafilter Geotextile.