Granite Paving Slabs:
9 Most Frequently Asked Questions
In this guide we will go through some of the most frequently asked questions we receive about granite paving slabs.
Some of the questions include; are granite paving slabs porous, if garden paving slabs are slippery, how to install granite paving and much, much more. Let’s start.
1. Are granite paving slabs a good choice for patios?
Granite is a very good choice for patios, it is an extremely hard wearing material and for this reason you will see it being used in shopping centres, city promenades, hotel verandas and increasingly a lot of domestic gardens.
Being a natural product the neutral colours of granite paving will blend in with and complement almost any garden or patio setting and won’t clash with the brick work or rendered finish of a house, no matter the colour.
2. Do granite paving slabs stain over time?
Because granite is a very hard non-porous stone it is not susceptible to staining, lichen growth or moss.
In terms of weed growth what happens is that seeds fall into the joints of paving and weeds can sprout up from there, that said, there are plenty of suitable grouts available which combat this problem and keep it to a minimum.
3. Are granite paving slabs slippery when wet?
Slippery Slabs are every clients worst nightmare! With the 364 days a year of rain in Ireland this is a very real problem and concern in this country.
The solution to this problem is to go for either a flamed surface or a bush-hammered surface finish on granite slabs. Both of these finishes have a slightly rough to the touch texture, great anti-slip properties but at the same time feel great under-foot when walking on them.
4. Which product is better? Granite paving slabs or concrete paving slabs.
Various dyes are used in the manufacture of concrete paving slabs, these can fade over time which can lead to your patio looking “jaded” after a few years.
Granite Paving Slabs are a 100% natural product and although they are more costly are a superior product. After all, natural granite has been used as a paving material for hundreds of years and has stood the test of time.
5. Does granite paving need to be sealed?
Opinion is divided on whether or not granite paving should be sealed.
Our advice would be not to seal it immediately but maybe a year after installation it could be cleaned and sealed. This will allow the granite to breathe and get settled into its natural environment first.
6. Can I lay paving slabs without cement?
Granite Paving Slabs have to be laid on a wet mix of sand and cement.
As with any Paving installation the sub-base takes all weight, it is vital that granite is laid on the correct foundation, this will ensure that your patio will look and perform optimally for years.
7. How To Lay Granite Paving Slabs
Follow these four steps to install granite paving slabs
a) The area to be paved must be dug out to at least 200mm in depth. Following this the area should then be back filled with 150mm sand/gravel 6 parts to one part cement, which is then to be compacted to 100mm.
b) After the complete preparation of the area to be paved is complete, the laying can start. The mortar bed must be prepared for each slab individually, depending on the depth/thickness that/each slab. A semi-dry mortar mix using 4 parts sand to 1 part cement is the necessary mix for the mortar bed. This ratio must be adhered to for natural stone to ensure it to have adequate support for the slab.
c) When installing slabs that will have mortar joints, ensure the receiving joints of the already laid slab are lightly lathered. As when the adjoining slab is placed it creates a strong joint, which can be further strengthened during the pointing process. Lathering the mortar will also help keep a consistent joint profile throughout the area. When the slab is in place, it can be secured by tapping it down with a rubber mallet. Constantly throughout this laying process you must check the levels to ensure uniformity.
d) Pointing (filling in the gaps) stage. With a wet mortar mix with a ratio of 4:1 building sand:cement, make sure that all the gaps between the slabs are completely filled. This is an important step to create a strong paving area, where there is a gap there can be weakness, removing gaps strengthens the area. While pointing, be careful not to use an excess as removing can be difficult.
8. Are granite paving slabs porous?
Granite is a very dense, non-porous paving material, because it doesn’t hold or soak in water it is very impervious to staining and discolouration.
9. Are granite paving slabs durable?
As a paving material granite is one of the most durable options out there on the market at the moment. All over the world there are hundreds, if not thousands of historical monuments and buildings that have utilised granite paving in some part of their construction.
Nearly all of these installations have stood the test of time, where a man made product will degrade over the millenia a natural material like granite will stand the test of time and be there even for future generations to enjoy.
This is it…
Granite paving slabs are a great addition to any garden patio that can last for generations..
Below are some photos of granite paving slabs installed in Ireland.
Let me know if you enjoyed this article by sending me an email. Please don’t hesitate to ask us for any information not provided above and I’ll get back to you as soon as possible.
Blog by Ryan Macey
Assistant Manager – Tile Merchant Ballymount