Blue Lias Flagstone Cleaning Shepton Mallet Somerset

Can an old Blue Lias Limestone Floor be successfully cleaned and sealed?

This is a case study of a Blue Lias Cleaning Shepton Mallet project, completed in May 2022

My client was searching for a Limestone cleaning polishing and sealing service for a well-worn Blue Lias flagstone floor in Shepton Mallet, Somerset.

blue lias cleaning shepton mallet
Picture of Blue Lias Limestone floor before cleaning polishing and sealing

Blue Lias Cleaning Shepton Mallet Project Background

The flagstone flooring is in an impressive period-property, dating to the early 18th century. The property is a family home brimming with wonderful original features.

Blue Lias stone has been used for centuries in the south west Somerset countryside and other areas.

It was used in manor houses and churches and Wells Cathedral.

Wells Cathedral

The flagstone is a fine-grained, muddy, iron-rich type of limestone, made up of limestone and shale layers. The stone has lots of fossils, especially ammonites. Flagstones can range in colour from cream to gray.

Blur Lias Flagstone Finish

When new, Blue Lias has a smooth even finish. However, years of wear can degrade the surfce of the stone as shown in this flagstone in a property in Westbury-Sub-Mendip, Somerset.

The floors in the kitchen, dining room and hallway I was working on, had suffered a great deal of flaking and wear. In some areas the surface had worn by 2 centimeters.

image of worn tiles on htis blue lias floor in shepton mallet

A few tiles had been replaced recently, between 5 and 20 years ago, and the surface of these tiles was lovely and smooth.

My client wanted the kitchen flooring, dining room flooring and hallway flooring cleaning and polishing.

The client was not looking for extensive restoration, like sandblasting or grinding, because they create a “like-new” finish.

They wanted the floor restored so that the renovation work preserved the natural beauty and character of the floor.

Deep Cleaning Blue Lias Flagstones

The tiles are categorised as Limestone, so I approached the work as I would with any limestone floor cleaning project.

I could see wax coating residues on the less worn tiles. So I used a broad spectrum sealer and coating remover. The product is designed to remove wax and acrylic coatings, and deep clean natural stone.

This stone is very porous and the surface is very uneven, so I decided to work in small sections. Working this way allows me to better minimise the amount of moisture soaking into the stone.

I gave the cleaner 20 minutes to soften the coating residues. The limestone kitchen floor and dining room floor were too uneven to use scrubbing pads. So I used a rotary scrubbing machine with heavy-duty scrubbing brushes. The scrubbing releases the coating residues and ingrained dirt from the pores of the stone. The slurry is quickly vacuumed off before it can soak back into the stone.

Deep Cleaning Blue Lias Limestone Floor In Shepton Mallet

The scrubbing machine could not reach some of the grout, so I completed the grout cleaning by hand scrubbing.

I rinsed the areas a couple of times with clean water. I removed the rinse water with a combination of a wet vacuum and dry microfiber cloths.

Then I moved onto the next area.

Cleaning the tile, stone and grout took 2 and a half days. I could have completed the work in 1 day if I had cleaned the whole floor at once. But cleaning in sections it makes sure the floor does not get too wet and allows the floor to start drying more quickly.

Sealing Blue Lias Flagstone Floor Tiles

After cleaning the first section of the floor, I test-sealed small areas with a neutral impregnating sealer, a color-enhancing impregnating sealer, and a stone oil. My client did not like the colour enhancing sealer and the stone oil samples. This particular flagstone has a lot of shale and mud particles. The colour enhancing sealer and the stone oil make the stone very dark.

My clients preferred the lighter, dusty finish of the newly cleaned stone, so they chose the neutral impregnating sealer.

Sealing Blue Lias Limestone Floor In Shepton Mallet

I completed the cleaning and resealing by applying 2 coats of our high quality impregnating sealer. I left the sealer overnight to dry.

The next day I tested the sealed limestone with a water droplet test.  After 20 minutes the water had not soaked into the stone.

Testing Seaoer On Blue Lias Limestone Floor In Shepton Mallet

I removed the water, and there was no ghost mark on the stone. This told me that there was enough sealer in the stone

Impregnating sealers stop water and oil spills from penetrating natural stone. But they do not stop acid and strong alkali spills from soaking into and staining the flagstones. A lot of liquids in a kitchen are acidic and alkali. So I suggested applying a thin coat of liquid wax to give added protection. A liquid wax can also be buffed to a lovely satin finish and it is easy to maintain.

Waxing Blue Lias Limestone Floor Tiles

I completed the cleaning and polishing by waxing the tiled floor. Floor waxes come in many forms. The wax I used on this limestone floor is a milky liquid.

I applied 2 coats of wax by hand, using microfiber cloths, leaving an hour between coats.

After another hour I buffed the wax to a pleasant satin finish using a rotary machine and a basso brush, which is similar to a brush used for polishing shoes.

picture of blue limestone floor in shepton mallet after waxng and buffing

The wax finish is easily maintained by adding a small amount of wax to a bucket of warm water and mopping it onto the floor after cleaning.

Grout Repairs On Flagstone Floors

The grout on this floor looks to be a lime-based pointing mix. On most of the floor, the grout looked to be in good condition. There were some areas of cement grout and a few small areas of lost grout on the kitchen and hallway floor.

We decided to fill the small areas of lost grout with colored floor grout. Ideally these areas should have been filled with a lime pointing mix, but there were time constraints, so my client decided to leave this renovation to a later date.

I carry a small supply of white grout and a range of cement dyes. I made up two colors of cement grout, dark gray, and mid-brown, to match the different colour tiles.

grout pointing blue lias limestone floor after cleaning and sealing in shepton mallet

To minimise mess and clean-up, I applied the grout using a mortar piping bag. Once the grout dried, I carefully removed the grout haze with a damp cloth.

How To Treat Newly Cleaned Blue Lias Flagstones

I left my client with some pH neutral cleaner and some floor wax. I explained how standard floor cleaners will quickly degrade floor wax and sealer, resulting in the stone staining and becoming dirty.. So it is important to only use a pH neutral cleaner. Once a month or maximum three months, depending on traffic, the wax finish should be topped up by adding some wax to warm water and mopping it over the floor.
If any areas of the floor are showing excessive wear, the finish can be restored by applying one or two coats of wax.

My client was delighted with the cleaning polishing and sealing renovation, enjoying the dog-friendly surface and experience of walking on the floor with bare feet.

If you need your stone floor cleaned and sealed

by a stone cleaning professional


Local Information

Shepton Mallet is a market town and civil parish in the Mendip District of Somerset, England, some 16 mile west of Bath, 18 miles south of Bristol, 5 miles east of Wells and 23 miles north of Yeovil.
It is a a vibrant market town, located at the gateway of the Mendip Hills. This area is an area of exceptional natural beauty. It is an ideal place to explore the hills surrounding it, which are criss-crossed by trails and footpaths, as well as the remnants of medieval and ancient industry and workings.

Shepton Mallet was once an important Roman town and route center. It is an ideal place to explore all that Somerset has to offer. Wells and Glastonbury can be reached nearby. The historic port of Bristol and the Roman city of Bath are both less than an hour away by car.

The town itself has an interesting history. The launch of a new series of heritage trails in 2021 highlights some of Shepton Mallet’s most treasured secrets. Visitors are immersed in the people, the industry, and a rich tapestry of the town. There is lots of information about the growth of the town since the Domesday Book.

Shepton-Mallet Prison is over 400 years old, with its own rich history. It housed the Kray Twins and Magna Carta during World War 2. You can now enjoy a tour with ghosts, escape rooms, and even a night behind bars at this visitor attraction.

All steam railway enthusiasts are welcome, including children and their families, at the East Somerset Steam Railway located just outside Shepton Mallet. To get an insight into steam’s world, take a train ride and stop by the museum, waiting area and ticket office. To see steam engines restored in action, visit the workshop and engine shed.

You can cool off during a hot day by swimming a few lengths, or having fun with the family in the Lido pool. The Lido is heated using recycled heat from Brother’s Drinks, a nearby cider and Perry maker.