Return to Products

Glass Blocks

Contact us for sales or technical advice on this product



Glass blocks are one of the most versatile building materials which suit practically every individual design idea.  With Glass Blocks you can choose from a vast array of sizes, colours and designs to find the ideal combination for all your building needs. Glass Blocks can be used both internally and externally.

Glass Blocks offer stunning visual effects and add style and value to your property.  Excellent fire rating, good sound reduction qualities and increased security are natural built in advantages.

Key Features & Benefits

  • Key Features & Benefits Quicktech System
  • Easy to Build – ideal for any capable DIY person to build. Full details are on each box
  • Stock items available within 2/3 working days
  • Extensive range of colours and finishes to select from
  • Shower proof after 4/5 days. Full strength after 1-3 weeks depending on room temperature
  • General Tools & Accessories Required


Technical Specification

Product sizes, weights & quantities

Block Type Flemish White Clearview F30 Sharah F30 F60
Size 190x190x80mm 190x190x80mm 190x190x80mm 190x190x160mm


1. What standard are glassblocks manufactured to?

To DIN 18175

2. Where can glassblocks be used?

Glass blocks are used inside or out side any building to increase light, improve visual effect, provide increased security (as they are reinforced). They are most effectively used in kitchens, bathrooms, reception areas, and stairways, dividing rooms, windows and hallways and to bring in light to dark areas of a building.

3. Where should I contact re-orders and deliveries/Samples?

Roadstone,  Architectural Products Division, Huntstown, Finglas, Dublin 11

Phone (01) 8581650

4. What should I state when ordering?

State size, pattern, colour, quantity, site directions, contact name and phone number. Our contact personnel will work out quantities if given panel sizes.

5. Can you give an estimated delivery time?

2-3 days from time of order for standard glassblocks i.e. Flemish or Clearview- 190 x 190 x 80mm.

2-3 weeks for other patterns.

6. Is there a minimum amount we will supply?

No, we will supply any quantities required by the customer no matter how small.

7. What are the standard accessories?

Building Mortar, Pointing Mortar, Expansion fibre, Sealant, Steel Rods available spacers,ex. stock.

8. What extra precautions should be taken during construction?

Ensure glass block walls are protected from wind, rain and frost while being built.

9. What sizes are available?

190 x 190 x 80mm is the most popular (95% of orders)

10. Can they be used to walk on/on floors?

No. We do not supply that type of glass block.

11. Are they waterproof when built?

Yes if built to correct specification.

12. What colours are available?

Generally-Azur, Blue, Turquoise, Light Green, Pink. See the brochure, as all blocks are not available in all colours.

13. What is the Pointing Mortar Colour?

White only.

14. How do I get around corners?

Use 90º corner units. Allow four weeks for delivery. Also 60-120º are also available.

15. Are there curved blocks?

Yes, you need two to turn thru 90 degrees.

16. Is there a maximum panel size?

Yes, usually 18m2 but much smaller if fire rated walls are required. Consultation with your local Roadstone representative is advised.

17. Where should one have control and movement joints?

On the sides and head, also every 6m lengths. Advice can be obtained from your sales representative.

18. What about condensation?

Within glass blocks it is not generally a problem.

19. What about mixing coloured blocks?

This can be done without difficulty. However the pointing mortar remains a white colour.

20. Can glass blocks or accessories be sold separately?

No, they are sold as a package but extra glass blocks and accessories can be ordered.

21. What weights are involved?

Product Amount Weight Pallet size
1 pallet glass block 360 glass blocks 900kgs 1m x 1m x 1m
Glass block Mortar 40 bags 25 kgs/bag 12.5

22. What should one use for reinforcing?

High Yield Stainless Steel rods (6mm and 8mm) are recommended, which are 3m in length. These are available ex.stock.

23. Who would you recommend to lay glassblocks?

A good bricklayer, preferably one who has laid them before?

24. How are they laid?

They are laid in special glass block mortar (10-12mm joints) with reinforcement vertically and horizontally in the joints (generally every second course) and pointed with the same glass block mortar. Glass block mortar is available from Roadstone.

25. Can I use ordinary cement mortar?

No it is not suitable . The Glass block Mortar has been specially developed for glass blocks.

26. How are they fixed to the wall?

The reinforcement bars penetrate the sidewalls to a depth of 40mm and act like a dowel. Consult your Roadstone representative for further advice.

27. Where is the expansion fibre used?

It is used at the two sides and the top of the glass block panel. It is a 20mm joint instead of the usual 10/12mm joint. One uses 10mm expansion fibre plus a 10mm-mortar joint.

28. Why is expansion fibre needed?

It prevents movement in the building cracking the glass blocks.

29. How much mortar would one require for say 100 blocks?

About 5 bags all together of Glass block mortar would suffice. You will need one bag of the glass block mortar for pointing . It is important to use the correct amount of water when mixing. This is printed on the bag. This is to ensure the correct consistency of the mortar.

30. How should the glass block panel be reinforced?

Normally the glass block panel should be reinforced fully with high yield stainless steel rods horizontally and vertically every second course. However you may need to refer to your engineer if you have any specific queries.

31. What joints do you recommend?

Usually 10-12mm horizontally and vertically.

32. Are they load bearing?


33. Are spacers available?

Yes, but they are not recommended for external work in case of water penetration.