Applying MicroDur Medium
Follow the directions below to apply the MicroDur Medium.
You can expect the 1st coat of MicroDur Medium to be dry enough to take a 2nd coat within 1 to 3 hours. There is no limit on how long you can leave it between 1st & 2nd coats. The pot life of MicroDur is 1-3 hours, so it’s best to mix it in batches.
Mix 10kg MicroDur Medium with 3.0-3.5l Water.
You will need a microcement mixer and a flexible trowel.
Mixing the 1st Coat MicroDur Medium
You will need 10kg of MicroDur Medium to complete 2 coats over 10m2.
If you are planning on applying both your 1st and 2nd coat on the same day (within 3 hours), you can mix them at the same time. We wouldn’t recommend that you mix more than 20kg at a time.
To mix 1 x 10kg batch, measure 3.0l – 3.5l Water using a measuring jug.
Pour the Water into your mixing bucket, and mix in the Colour for 10kg MicroDur Medium.
Use the Water to rinse out all of the colour from the bottle.
Add 10kg MicroDur and mix thoroughly.
Let the mixture rest for a few minutes before applying. Keep a lid on it between coats. You can loosen it up before applying your 2nd coat by giving it another mix.
If you’re not going to apply the 2nd coat on the same day, then split the colour/water mix and the MicroDur Medium into 2 equal batches and mix the 2nd batch fresh when you’re ready to apply it.
Applying the 1st Coat MicroDur Medium
Using a Microcement Trowel, work your way out from one corner creating a random edge pattern. Keep trowel movements small and random, avoid long sweeping arches – as these will show through to your final finish.
Use the grain in the microcement as your level – if you apply the microcement thicker than the size of the grain, the finish won’t be as strong and will require a lot more sanding. Run the trowel back over each section that you have put down to smooth it out and remove excess product.
Completely cover each surface without stopping. For complete rooms, start with ceilings, then walls from left to right (or right to left) and then the floor.
Run your finger or a corner trowel along internal corners to push the microcement into the corner and then gently trowel away the excess product.
Getting the Right Effect
The more you trowel over the microDur with a steel trowel, the more it will blacken in high spots. This technique is called “burnishing” and is often used by microcement installers to add depth to their work.
This looks great in grey-scale colours but isn’t always desired in lighter or brighter colours. So if you don’t want black marks, try not to trowel over the same area more than you need to.
To achieve a cloudy texture, you can use the “Fresh on Fresh” technique with MicroDur Medium. Go straight on with your 2nd coat of MicroDur Medium within 30 minutes – 1 hour of applying your first coat. With the right amount of pressure on the trowel, you will be able to blend the 2 coats together and achive the cloudy finish.
You can use high density foam boards to walk on. This will prevent you marking the floor with your shoes.
Mixing 2nd Coat MicroDur Medium
You will need the same number of batches that you used for your 1st coat.
For each batch, measure 3.0l – 3.5l Water using a measuring jug.
Pour the water into your mixing bucket, and mix in the Colour for 10kg MicroDur Medium. Use the water to rinse out all of the colour from the bottle – to avoid colour variation between batches. Add 10kg MicroDur Medium and mix thoroughly.
Let the mixture rest for a few minutes before applying.
Mixing Smaller Batches
You will need 1kg MicroDur Base per m2 per coat & 500g Top Coat per m2 per coat. So for 2 x base coats & 2 x top coats, you’ll need 2kg Base Coat & 1kg Top Coat.
The best way to split the colour for MicroDur Base, Medium or Fine is to measure out the full amount of water for 10kg microcement & then add the colour for 10kg Microcement to it. Make sure you get all the colour out of the bottle and stir it in well.
Then you can take the amount of water that you need for each kg & be confident that the colour will be consistent across all the batches.
Applying 2nd Coat MicroDur Medium
Apply the 2nd Coat of MicroDur Medium in exactly the same way as the 1st coat. It’s crucial that you go as thin as the grain with MicroDur Medium.
Leave to Dry
The microcement needs to be fully dry before sealer is applied. If not the microcement will not reach full hardness and could de-laminate.
Moisture content should be less than 5% before sealer is applied.
The timings below are for guidance only, your microcement may take longer to dry depending on temperature and humidity.
Leave MicroDur to dry for at least 24 hours.
Sand with 220/240 Grit Sand Paper
Gently & evenly sand the surface of the microcement with a 220 or 240 grit paper to remove any rough patches and drips. It should be flat from the trowel so you shouldn’t need to sand it too much at this stage.
Vacuum the surface to remove all dust and debris. Do not wet the microcement.
Microcement Sanding Discs are available from Relentless Microcement.