How to reduce dust when cutting concrete?

[elbow]

Hey Guys & Girls

I need to build my sills and architraves for my new double-glazed windows but i need to cut the surrounding concrete lower as per the pic - However, i have a grinder that i can use to cut along the concrete but I'm worried about the amount of dust and was wondering how i can reduce the dust or at least prevent the dust from getting all over the rest of the room. I know i can fit a hoover attachment to the grinder but they're a bit expensive for my current budget at $60-$70. Perhaps plastic sheets from the ceiling down to the floor to create an enclosure around the windows, i dunno. Any suggestions or ideas would be hugely appreciated  🙏

cut this down to lower level

[EricL]

Hello @elbow 

Thanks for sharing your question about how to reduce dust when cutting concrete. Your idea of creating a small enclosure with drop sheets and masking tape is actually how trades people prevent dust from overwhelming the entire house. 

It is unavoidable some dust will get out, but at least it will be greatly reduced and confined within the drop sheet space. Another solution is to have another pair of hands holding the shop vac hose at the back of the concrete cutter where the dust gets expelled.

I propose looking at the Ozito 1250W 12L Stainless Wet And Dry Vacuum which I believe fits neatly into your budget. It doesn't need any special fittings and if luck is on your side, it might even fit your grinding tool.

Let me call on our experienced members @Dave-1 and @TedBear for their recommendations.

Please make sure to wear personal protection such as gloves, goggles and a Citeco Half Face Respirator A1P2 Kit when working on your project.

If you need further assistance, please let us know.

Eric

[wooshka]

Hi @elbow , I have done this a number of times both inside and outside houses, believe me you will dissapear in the dust a dry cut off blade will create, especially inside the house.

you will need a proper filtration mask to wear as well as i would even recommend a full face ventilation mask as the amount of dust overloads normall dust masks.

the other thing i have found is that most vaccuum type devices block up really fast from the dust so they stop working after a short time.

If you can a wet saw for inside is the way to go if you can afford it.,if this can be done with the water doning damage

if it cant be just tape off as best as you can, but the dust seems to get through every nook and cranny.

[Nailbag]

Hi @elbow don't under-estimate the spread of dust cutting masonry will cause throughout the home. It's extremely fine and abrasive. So the main things to prepare for would be:

100% only use a workshop vacuum and not a domestic one as per @EricL . Masonry and plasterboard dust will find its way in to any electrical motor and cause irreparable damage to a domestic vac. Workshop vac's use a bypass motor system that will collect the debris without harm to the motor. Ensure you clean the filter regularly but not with water despite what the instructions might state. Moisture and masonry/plasterboard dust will simply clog the filter. Just give it a good tap and brush. I would also recommend a pre-filter bag over the main filter to provide a cleaner work environment and easier cleaning process.

Ensure your wearing a P2 rated dust mask, eye protection and earmuffs, to keep the dust out.

When sealing the room, fully tape the drop sheet firmly and close any windows and doors to prevent any breeze.

When using the grinder, hold the tip of the vac with a crevice tool fitted to the debris side of the guard to maximise the effectiveness of the dust being removed.

Regards, Nailbag

[elbow]

thank you for this sound advice, there are some good tips here and a couple things to look into. very much appreciated 🙏

[elbow]

awesome advice, thank you so much - yeah the mask is essential. i did a small section a few weeks back and the dust-cloud is incredible! i think the wet method is beyond me but will look at any ways i can do it. much appreciated 🙏

[TedBear]

Hi @elbow,

I can't add much to this conversation.

When we had a doorway cut out through an internal brick wall I watched the workers disappear into a dust cloud, so I made an escape path for the dust by opening up doors and put two upright fans (on high speed) next to where they were working, pointed at the open doors. These blew air and dust forcefully out of the doors.

That reduced the cloud somewhat, so at least the workers didn't disappear while cutting and less dust was able to settle.

Perhaps something like that is a possibility in your case.

[elbow]

possibly altho the only route is out the windows - unfortunately the middle and largest window is a whopper and fixed/closed 

[TedBear]

Using that window  as an outlet should do. Can you work from the inside?  I find that fans are better at shifting dust to where you can manage it, than vacuum cleaners are at sucking it up. (VCs only work on dust that exists at the point of vaccum intake, which is a small area.) Of course, using both would give you the best chance of minimising the dust.

[Dave-1]

Evening @elbow 

Grinding concrete dosnt sound like a lot of fun I must admit. I havnt done any so cant really help you out other then misting over the area with a water spray as you grind is about all.

Looking at your sill, is there a way around to install the type of sill you want without needing to grind the concrete right back?

As in a face type deal  for the front of the window and with the sill level lifted up using spacers or other timber pieces?

Dave