
Concrete Decking Block Shims
Ensure that your concrete decking block subframe is in harmony with your joists or battens to create the perfect decking area. Concrete post spacers give a spot on fit and allow your joists to fit into the foot with room for expansion.
More About our Concrete Decking Block Shims
Want to ensure that your joists are well-fitted when using concrete decking blocks in your decking installation? Using these decking block shims is the way to go. They help to properly adjust the posts when fitting into concrete feet to create a consistent expansion gap.
Specifications:
- Length: 78mm
- Width: 30mm
- Depth: 8mm
- Number Per Pack: 48
Creating an appropriate gap ensures your joists have room to naturally expand and contract with changes in temperature and moisture. This helps to prevent common issues such as squeaking, warping, or buckling over time.
Each shim is designed to interlock, allowing you to build up to your desired thickness. This ranges from 2mm to 16mm so that you can customise the gap to the project requirements.
Quick Reminder: Make sure to remove all shims before laying any decking boards on top of the system.
Order A Sample Pack!

Download the datasheet for Concrete Decking Block Shims
Type | When? | Cost? | ||
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National Delivery | Orders under £1,000 | Est. 5 working days* Roofing items 7-10 working days* |
£192.00 |
Orders over £1,000 | Est. 5 working days* Roofing items 7-10 working days* |
£96.00 | ||
Orders over £1,500 | Est. 5 working days* Roofing items 7-10 working days* |
FREE | ||
Scotland Delivery | Est. 15 working days* Roofing items 7-10 working days* |
£360.00 | ||
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Millboard Delivery | Orders under £2,000 | Est. 5 working days* | £192.00 |
Orders over £2,000 | Est. 5 working days* | FREE | ||
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Parcelforce Standard | (Small Parcels) | 3-5 working days* | £8.50 |
Parcelforce Standard | (Large Parcels) | 3-5 working days* | £30.00 | |
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Sample Packs via Courier | 5 working days* | FREE |
*Please allow for public holidays and weekends (non-delivery days)
Some of our products are available for collection from our warehouses in Okehampton (Devon) and Andover (Hampshire) - This option will show at checkout, when available.
Standard collection lead time is 3-5 working days, this may vary depending on the product. If you would like to collect your order after 2 hours, please choose this option at checkout.
Please note that collections are only available from Monday-Friday, 08:00 - 17:00 & Saturday, 08:00 - 12:30 (Note: this IS the cut off time for collections, despite our closing time of 13:00)
Please Note The Following Prior To Collection:
Vehicles we can and cannot load
Cladco Profiles will only load flatbed lorries and flatbed trailers for insurance purposes. If the appropriate vehicle is not available, two people would be required for a collection.
Cladco Profiles will NOT load any vehicles with roof racks, horse boxes, cattle lorries or fixed-sided trailers. Cladco Profiles has the right to refuse loading a vehicle for any reason.
Before arranging a collection, please read our Customer Collection Notice below.

Our Okehampton HQ and Warehouses (Devon)

Our Andover Warehouses (Hampshire)








Customer Collection Notice
For those customers wishing to collect materials, we ask you report to the office first in order to be seen by a member of the sales team. Your goods will then be picked and brought to your vehicle.
Please note that during busy periods you may experience a wait while our yard staff serve other customers or are loading/unloading other vehicles.
We respectfully draw your attention to the following points:
- It is the ultimately the responsibility of the customer to load his/her vehicle and to ensure the goods are safely/ securely strapped down.
- Our staff will be happy to assist you load your goods onto appropriate vehicles by way of fork lift trucks. Our staff will not handball any goods into enclose vehicles. The loading of the vehicle is carried out entirely at the customers own risk. We will not be held liable for any damage that may occur to your vehicle or goods collected from our premises during the transport of said goods.
- It is the responsibility of the customer to ensure both their vehicle and the goods are safe when they leave our premises.
- We can advise the approximate weight of materials prior to you arriving so that you can be sure your vehicle is capable of carrying the intended load. Please ensure that you bring appropriate ropes, straps or other securing materials as we are unable to provide you with any upon arrival.
- We strongly recommend you bring suitable protection materials to prevent your ropes/straps etc. be damaged by these edges. We recommend that you use good quality protective gloves when handling materials.