Green-tree Roof Garden Subsoil

Roof garden subsoil is a specially designed blend to complement and work in conjunction with our Intensive and Podium Deck Roof Garden Substrates as a base to build up the substrate profile.


The product is a blend of lightweight aggregate and specially selected washed silica sand. The sand has been specifically sourced to give the substrate optimum drainage properties, which works well with the drainage needs of the green roof substrate whilst offering good levels of aeration.

Benefits of Green-tree Roof Garden Subsoil

Lightweight and easy to install
Lightweight soils are much easier to manage. They are easier to spread and work with. These soils benefit vegetation establishment due to their open structure.

High quality ingredients
Lightweight aggregate promotes strong root development, improves aeration and drainage. Silica enhances the strength and rigidity of plants to help reduce pest damage.

Optimal drainage properties
Drainage properties enable the water to move freely through, and be soaked up by, the soil and carried to the plant’s roots and stems for a healthy and established roof garden.

Good levels of aeration
With lightweight aggregate being incorporated into the blend, this opens up small holes and gaps within the soils structure to allow air, water and nutrients
to the plants.

Guaranteed quality and consistency
This blend of subsoil is high quality which provides added reliance to perform exceptionally on a green roof environment under strong and harsh weather conditions.

Nationwide availability
We supply Green-tree Roof Garden Substrates across the UK to some of the most complex and impressive green roof projects we have in this country.

Typical Analysis of Green-tree Roof Garden Subsoil

pH 6.7
Total Porosity 40%
Saturated Hydraulic Conductivity 720mm/hr

 For the latest analysis and bulk density of this product please contact our team.

NBS Clause

Section Clause NBS Clause Title
Q28 330 Imported manufactured topsoil/growing medium
45-40-85 340 Special imported topsoil and growing media


Green Roof Calculator

Please enter the dimensions of the area you wish to fill (in Metres).

*The figures provided by the calculator are a guide only, we advise contacting one of our specification team to discuss your project requirements in full.