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⚡ Rock Bottom Prices. Maximum Choice.⚡
⚡ Rock Bottom Prices. Maximum Choice.⚡
Holcim Postmix 20Kg Bag

Postmix 20Kg Bag

Shop All Holcim
SKU 22020
£6.99 - £6.99
£6.99
£6.99 - £6.99
£6.99
✓ In stock in NorthamptonCollect in 1-2 hoursDelivery in 1-2 working days
✓Cheaper than Wickes, B&Q & Toolstation
Wickes price £7.50You save £0.51
Compared with their equivalent: Blue Circle Ready To Use Postcrete - 20kg
B&Q price £7.50You save £0.51
Compared with their equivalent: Blue Circle Postcrete, 20kg Bag - Ready mixed
Toolstation price £7.49You save £0.50
Compared with their equivalent: Blue Circle Postcrete 20kg
Prices checked 24 Oct 2026 on their websites. Excludes delivery. How we check
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General Purpose Cement 25KG
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In stock at Rock Bottom Northampton
Click & Collect — Rock Bottom Northampton Ready in 1-2 hours · FREE
Van delivery — our own van, within 10 miles £19.99 on orders over £100 · too big to post, so we bring it ourselves. Pick your day and hour in the basket.
Frequently bought together
ForgeFix Coach Screw Hexagon Head Single Thread ZP M8 x 200mm Bag 10 £7.49
Sawn Feather Edge UC3 125 x 22 x 1800mm £1.85
You'll also need
Sawn UC4 Treated Fence Post 75mm x 75mm x 2400mm
FencingSawn UC4 Treated Fence Post 75mm x 75mm x 2400mm£10.49 See all fencing →
Grange GSL6 Superior Lap Panel 1.8m
FencingGrange GSL6 Superior Lap Panel 1.8m£37.99 See all fencing →
General Purpose Cement 25KG
CementGeneral Purpose Cement 25KG£7.70 See all cement →
All building materials →

Description

Post Mix Concrete is suitable for use in fixing all types of wooden, metal and concrete posts.

The mix is a kiln-dried, pre-blended, factory-produced quick-setting concrete, which hardens in approximately 10 minutes after water addition, depending on ambient conditions.
🔨 Trade Prices for Everyone

Why pay more? We keep our prices rock-bottom so whether you’re a trade professional or DIYer, you always get the best deal.

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We’re Northampton’s trusted family-run store, supporting local people with great products and honest service.

🚚 Easy Pickup or Local Delivery

Order online and collect in-store, or get heavy items like blocks and cement delivered straight to your site.

👍 Friendly, Helpful Service

Our staff know their stuff — whether it’s building materials, DIY or garden, we’re here to help you get the job done.

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