If you're lucky enough to live in the UK and have a flat roof that you can take advantage of when the weather allows it, but choose not to, then a deck may be the PERFECT thing to change your mind! 

Installing a composite deck from DeckPlus on your flat roof not only offers a fantastic flooring option that is suited to all weather conditions but a flooring option that is easy to install and will last the test of time with warranties up to 30 years. 

If you are planning on installing a deck onto a flat roof, however, there are a few things that need to be considered before-hand, including your roof's construction. There are several types of flat roof construction, typically, these are:

  • Inverted roof systems 
  • Mastic asphalt 
  • Layered asphalt 
  • Concrete 

A deck installed on each of these roof types requires its own installation method. Here are some recommendations that you can follow if thinking about installing a deck on your flat roof.

Inverted Roofs

Many of these roof systems contain a top layer of PVC. It is not advised for this layer to be in direct contact with any rubber products that could help with installation (such as EasyFix rubber joist shoes). Therefore the use of additional supports such as roof tiles is recommended to separate the PVC and rubber products. The has the added benefit of distributing the load over a greater surface area.

Inverted roof


Mastic Asphalt Roof 

As a result of these roofs being 'soft', it becomes necessary to spread the load placed on them. This is achieved again by installing a supporting product such as a roof tile in between rubber products and the asphalt.

Mastic asphalt roof


Layered Asphalt or Concrete Roof

If a concrete roof is finished with a PVC-based water-proofing then rubber support products will be required to be isolated from the PVC asphalt roofing felt with a roof tile.

Concrete roof


TimberTech EasyFix Shoes 

These rubber supports are designed for use with floating decks on concrete slab areas - particularly roof terraces, balconies, flat roofs, paved areas and around swimming pools and hot tubs. EasyFix shoes have been used on a number of prestigious developments in the UK, offering a variety of benefits such as:

  • Allowing a deck to float on concrete slabs eliminating the need to mechanically fix the slab with a resultant danger of piercing weatherproof membrane. 
  • Easily levelled using associated packers. 
  • Creates a moisture barrier between slab and deck battens. 
  • Improves drainage on slabs as deck battens are raised. 
  • Removes chances of timber battens sitting in standing water.
  • Effective acoustic-limiting properties - ideal if you have living accommodation under the decked area.
  • Easy to install! 

EasyFix shoes


Installing Deck on a Flat Roof Tips

  1. Choose what height timber batten to use, paying close attention to the height of any existing door threshold. 
  2. Push-fit EasyFix shoes at gaps of 400mm down the length of timber battens (8 per m2 recommended).
  3. Layout timber battens.
  4. Allow expansion gaps of 10-15mm between each length of timber batten if more than one length is required.
  5. Fix a timber batten noggin at intervals of 1.2m
  6. Use EasyFix packers to assist with levelling the deck


Installing your deck on a flat roof is really that simple! For more information or guidance on how to install your new composite deck boards on your flat roof, be sure to contact the DeckPlus team today! Did you know you can now order your composite decking directly through our website? Browse our full range of composite decking here!

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