Lancashire Stone Expert Details how to Resurface Old Flagstones using Coarse Milling Pads

 The client said when he moved into this house in Lytham St Annes late last year that this room had a really bad smell of damp. The Flagstone floor was covered in carpet and he had the impression that the previous owner’s cat had been known to use it as place to pee!

   

The smell was rank and probably bad for your health so he decided to remove the carpet and the thick underlay underneath. Under that there was some old Vinyl flooring which all came out to reveal the original flagstone floor. As you can see from the pictures it was in a poor state covered in red and white paint, bits of bitumen here and there and the pointing had been lost in several areas of the floor. Additionally, all those layers over the stone would have prevented any moisture from naturally evaporating at the surface thereby resulting in damp.

 

The client had seen what we could do on our website and sent us some pictures of his floor which covered approximately 16m2. I priced for milling the flagstone as a deep clean would not resolve the shaling issues on its own and only a good mill of the stone would do that. Also, it needed all the pointing that was still in place knocking out and new flexible breathable pointing put back in place.

 

Cleaning and Repairing a Flagstone Tiled Hallway Floor

Milling stone is not a low-cost option, but it is a lot more cost effective than pulling up the whole floor and putting in a modern subfloor. Milling involves using a weighted buffing machine fitted with different grits and grades of coarse Diamond encrusted pads which cut into the surface of the stone to reveal new stone underneath, you then apply finer pads to hone and refine the surface.

In this case I used a set of Tile Doctor Milling Pads applied in sequence starting with 50-grit, 100-grit and then 200-grit. Water is used to lubricate the process and keep the dust down, it’s also important to rinse the stone off after each pad and extract the slurry that is generated with a wet vacuum.

The floor was then cleaned with Tile Doctor Remove and Go allowing the product to soak in for ten minutes to loosen deep seated paint staining. The Tile Doctor Remove and Go was then worked in with another 200-grit pad before another rinse and extract again with the wet vacuum.

Older floors like this were installed before the invention of the damp proof membrane so moisture is always a concern. To counter any issues that might develop later such as Efflorescence the last step in the cleaning process was to give the floor an acid rinse using Tile Doctor Grout Clean-up, this neutralises any latent salts trapped in the subfloor.

 

Sealing a Flagstone Tiled Hallway Floor

The milling, re-pointing and cleaning work took two days and we returned for a third day to apply a breathable sealer called Tile Doctor X-Tra Seal. This product is fully breathable and a great choice for any floors where damp can be a problem as it will allow for moisture to rise through the stone and evaporate at the surface. Being oil-based it also adds character to natural stone and adds an appealing low satin finish.

 

The whole process completely transformed the appearance of the flagstone floor and really suits the property which was a late Victorian four-story house with a basement. Original features like this are very sought after so it makes sense to restore them as it will add value.

 

An additional advantage of the milling process is it also reduces the roughness of the stone surface makes it smoother and easier to clean. On the topic of cleaning its worth mentioning that you should never use a strong bleach-based tile cleaning product on a sealed floor as it will erode the sealer prematurely. For a floor like this you need to use a product like Tile Doctor Neutral Cleaner which is a mild but effective cleaning product designed for use on sealed tile and stone.

Source: Flagstone Floor Restoration Services in Lytham St Annes Lancashire

How to Remove Screed and Bitumen from Stone Floors

The owner of this Flagstone floor at a property in Carnforth was told by a damp specialist to remove the carpet and underlay and have the floor taken out and skipped. Then to install new hardcore and concrete put in place but with a Damp Proof Membrane installed in between, then once fully cured (four weeks at least) they could have a new carpet, tile or wood floor etc. installed. All good advice, however, the owner of the house wanted to keep as many original features as possible and wasn’t keen on the proposal.

Looking for an alternative solution they reached out to Tile Doctor and so I went over to take a look. After surveying the floor, I came up with a completely different solution which involved milling the stone with coarse abrasive pads to remove the screed and bitumen and then resurface with diamond encrusted burnishing pads of medium and fine grits which would result in a smooth finish. Not only would this be much easier to clean going forward it would also be much more attractive, especially once sealed.

 

Happy with our alternative we arranged a date to come and do the work which would take three days, two days to prepare the floor and a third to apply a sealer.

Cleaning a Flagstone Tiled Ground Floor

Milling a floor is arduous work and requires the use of a heavy rotary machine that can apply weight onto the stone so the milling pads can really get a bite into the surface. Because of this I roped in a colleague to help take some of the strain. Some of the areas of bitumen and screed were so prominent we used an SDS hammer action drill with a flat bit to chisel them off first, this can leave a few marks in the stone which we then level out with the milling pads starting with a 50 grit and go all the way up to a 400 grit.

We used a lot of water during this process to help lubricate the abrasive action of the milling pads, this also helps to rinse off the soil that is created, all of which is extracted with a wet vacuum.

Next step is to give the floor an acid rinse with Tile Doctor Grout Clean-Up which is designed to neutralise any alkaline salts in the stone that could result in efflorescence later.

With the floor cleaned up the last step was to re-point between the Flagstones using a breathable pointing product called GFtK 800.

 

Sealing a Flagstone Tiled Ground Floor

Sealing was the next step however the floor was still quite damp after the initial renovation, so it was left for a few days to dry out first.

We selected a fully breathable sealer for this floor, this is an important requirement for a floor with no damp proof membrane as it will allow moisture to rise through the flagstone and evaporate at the surface. The concrete screed and bitumen covering will have prevented this previously which is dangerous as a build up of moisture in the stone can lead to it crumbling and you risk moisture reaching out to the walls where it can lead to rising damp. 

Tile Doctor has three breathable sealers to choose from and in this case the customer decided to go with Tile Doctor Colour Grow which is an impregnating sealer that protects from within and enhances the natural colours in the stone.

  The floor was completely transformed by the end of the third day, you would not have known it was the same floor. It was now clear of all the previous coverings and now looked like a characterful old Flagstone floor should.

Before leaving I recommended, they use Tile Doctor Neutral Cleaner for everyday cleaning, being pH neutral it won’t prematurely erode the sealer allowing it to work for longer. I also advised that it’s possible that parts of the stone may go a shade darker in winter and a shade lighter in summer due to the moisture rising through the floor.

Source: Stone Floor Restoration Service in Lancashire

How to Renovate Old Flagstone Flooring

I was contacted by the owner of this property in Leeds about renovating their old Flagstone floor. The couple who owned the house both worked long hours so after discussing the floor at length over the phone and after reviewing several photographs they emailed me to ask me to go ahead and start work. I normally prefer to do a site visit beforehand so I can provide an accurate quote, clearly however this wasn’t going to possible in this case.

The owner had arranged for his father in law to let me into the property so I could start work. I was aware from the phone calls we had that there was an issue with the pointing, and I was prepared for this, but it was worse than I had anticipated with most of the grout missing or loose. Interestingly the stone was quite yellow and so probably came from the Salts Mill area near Leeds. Sir Titus Salt was a 19th century industrialist and philanthropist built a large textile mill out of the stone. The mill is now a centre for art, dining and shopping and well worth a visit if your passing.

Cleaning and restoring a Flagstone Tiled Kitchen Floor

I decided to deal with the floor cleaning first and began by scrubbing the flagstones with a strong dilution of Tile Doctor Pro Clean using a rotary floor machine fitted with a scrubbing pad. The soil was then extracted using a wet vacuum and flagstones re-inspected. The remaining stubborn stains were spot treated using a repeat of the previous process until I was happy they were as clean as they could be. As the floor dried I took out all the loose pointing and re grouted the whole floor with a mid grey grout which matched the old flagstones quite well. The floor was now looking vastly improved. The floor was then left to dry fully overnight to ensure the seal could be applied.

Sealing a Flagstone Tiled Kitchen Floor

I returned the following morning and tested the floor with the moisture meter, I was satisfied the floor was within the accepted parameters and we could now apply the sealant. I selected to use a couple of coats of Tile Doctor Colour Grow, allowing each coat to dry before applying the next one. This product enhances the colour but leaves a matt finish. It will form a durable protective seal to the floor which will ensure the floor is easier to maintain.

I heard from the later that they were over the moon with the result and as part of the conversation we discussed the best way to maintain the floor going forward. Basically, this involves being careful with what you use to clean it as strong products can weaker the sealer. I recommend they use Tile Doctor Neutral Tile Cleaner which is pH neural and designed for the regular cleaning of sealed tiles.


Source: Flagstone Floor Cleaning, Sealing and Renovation Service in North Yorkshire