Sudspave® Porous Aggregate Surface

Structural design, installation and maintenance guidance

Sudspave is a recycled plastic cellular porous paving solution for use in Sustainable Drainage Systems (SuDS). Sudspave is suitable for a wide range of trafficked applications where a stabilised, free-draining gravel surface is required. Typical applications include: car parks, emergency access, maintenance routes, cycle paths, pedestrian and disabled access. Considerations relating to the movement and attenuation of water within the porous pavement are not covered in this document. This document is intended to be a summary presenting typical solutions. Contact ABG for detailed site specific advice.


The following generic guidance must be read in conjunction with the specific project specification within the contract documents

Sudspave gravel design and installation guidance

1. Install the specified lower filter/separator ABG Terrex NW9 geotextile and sub-base stabilisation onto the prepared subgrade formation.

2. Install the specified sub-base and edge restraints.

3. Install the upper filter/separator ABG Terrex NW9 geotextile geotextile on top of the sub-base.

4. Install the specified bedding layer to a uniform thickness.

5. Ensure an accurate right-angled Sudspave laying pattern by setting-out the site using pins and string-lines. Check the lines regularly for accuracy. Start installing the pre-assembled Sudspave panels (4 units/m²) by placing the webbed face downwards onto the bedding layer. Place the panels with the T-shaped lugs facing in the direction of laying on the two leading edges, with the clip-slots on the reverse-edges.

6. Progress across the site in rows by slotting panels together in a downward motion, ensuring that the 8 self-lock clips-slots engage fully with the T-shaped lugs on adjacent panels.

7. Avoid starting more than 2 new rows of panels prior to completing the row which is in progress. Avoid installing in a diagonal pattern too far ahead of completed rows. Regularly check and adjust the completed leading edge to ensure that it is straight. It is recommended that protective gloves are worn to avoid abrasions during installation.

8. Individual paver units can be separated if required. Insert the tip of a flatblade screwdriver between each side of T-lug and the slotted paver-face in turn. Gently twist the blade to dislocate each clip-lock & lug, whilst lifting the slotted unit up and apart. Do not force clips open or pull pavers apart as this will break clips.

9. Sudspave can be cut to fit around curves or obstacles using a hand-saw or disc-saw. Using cut-pieces which do not have integral T-lugs & clips should be avoided wherever possible. However, if use of small pieces is unavoidable, these must be securely attached to adjacent panels using
strong cable-ties or appropriate screws.

10.Installation of parking bay/line marker inserts is best done prior to filling cells. Push markers into the round cells until they click and lock into place. Rotate slightly to fit if required.

11. Fill the cells with the specified aggregate, so that the final level is to the top of the cells. If placing pavers and filling the cells simultaneously, it is important to keep bulk materials and vehicles away from the leading edge to avoid distortion. Do not drive vehicles on the installed panels until cells are filled with aggregate. Do not over-fill or surcharge the cells unless specified by the designer.

12. After initial settlement and trafficking, aggregate may need topping up.

13. A routine management and maintenance programme to keep the surface in good condition and free of debris and weed growth, will help to sustain the porosity, quality and longevity of the system.


a.  Advice on subgrade CBR% strengths, ground conditions, and construction over weak ground is available from ABG.

b.  Alternative ABG stabilisation geosynthetics may be used in lieu of ABG Abgrid geogrid. These include ABG Gridtex Type 2 high-strength woven geotextile or ABG Abweb geocells. If the sub-base stabilisation is omitted, the total sub-base layer thickness (‘D’ on Table 1) is typically increased by a minimum of 50%.

c.  A permeable open-graded (reduced-fines) aggregate is recommended, such as DTp Type 3 low-fines roading aggregate, or BS 7533-13:2009 SuDS aggregate (4/20 or 4/40). However, where a conventional DTp Type 1 sub-base is to be used, it is essential that a drainage system such as ABG Fildrain is incorporated. Specific advice is available from ABG.

d.  Maximum sub-base particle size should match minimum sub-base thickness but must not exceed 75mm diameter. For sub-base thicknesses of around 100mm, a minimum 37.5mm particle size should be adopted to allow effective installation of the Abgrid.

e.  Typical paving edge restraint solutions include: concrete, timber, railway sleepers, steel and heavy-duty plastic.


f.  The sub-base may be overlaid by an ABG Terrex NW9 geotextile to provide enhanced water treatment function if required.

g.  To provide a stable bedding layer for Sudspave, the bedding layer must not be sand.

h.  The maximum advised gradient for vehicular trafficked applications is generally 12% (1:8) 7°. For Disabled access applications, a maximum of 8% (1:12) 5° is suggested.

i.  When designed in accordance with the recommendations, Sudspave complies with BS8300:2009 : “Design of buildings and their approaches to meet the needs of disabled people” – Code of Practice (ISBN 9780 580 57419) & Building Regulations Document ‘M’ Section 6.

j.  All stated dimensions & weights are nominal and in accordance with manufacturing +/- tolerances.

k. The recommendations in this document are only suitable for use with ABG products.

Table 1: Sudspave® typical DTp Type 3 sub-base thickness (D) requirements – refer to specific construction drawing

Application/LoadCBR (%) strength of subgrade soil (Table 2)(D) DoT sub-base thickness (mm)Abgrid Geogrid
Light vehicles with emergency HGV access6+100
Light vehicles with one HGV per week

Table 2: Field guidance for estimating sub-grade shear strengths

CBR (%)
DCP Result 1 (Sandy Soils)
HSV Result 1 (Clayey Soils)
Tactile (Clayey Soils)
Visual (Clayey or Sand Soils)
1<1<30 kPa
Easily indented by fingersAdult standing will sink >30mm
30-60 kPaIndented by strong finger/thumb pressureAdult standing sinks 10-30mm
60-120 kPa
Cannot be indented by thumb pressureUtility truck ruts 10-25mm
2-3120-200 kPa
Can be indented by thumb pressureLoaded construction vehicle ruts by 25mm
>3>200 kPa
Difficult to indent by thumb nailLoaded construction vehicle ruts by <10mm

Note: 1. DCP results are expressed as blows per 100mm penetration. HSV results are expressed as “undrained shear strength” or Cu

Sudspave Permeable Pavers

Sudspave is a permeable paving grid system of interlocking cellular plastic porous pavers designed for the stabilisation of trafficked grass or gravel surfaces. Used where a free-draining permeable gravel or grass car park, access road or driveway is required.


Sudspave plastic porous paving grid for permeable trafficable gravel or grass surfaces


Sudspave Permeable Pavers

Sudspave is a permeable paving grid system of interlocking cellular plastic porous pavers designed for the stabilisation of trafficked grass or gravel surfaces. Used where a free-draining permeable gravel or grass car park, access road or driveway is required.


Sudspave plastic porous paving grid for permeable trafficable gravel or grass surfaces


All information is supplied in good faith and without charge to enable reasonable assessment of the practical performance of ABG products. Final determination of the suitability of information or material for the use contemplated and the manner of the use is the sole responsibility of the user. As design and installation is beyond the control of ABG (unless specifically requested) no warranty is given or implied and the information does not form part of any contract. ABG reserve the right to update the information within at any time without prior notice. ©2017 ABG Ltd


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