Installing a Basement Window - Cutting Concrete Block Foundation

[Music] [Applause] we recently were asked if we were interested in taking on a job of cutting a concrete block basement wall to install a window the client had an existing window single pane glass already there but it was too narrow and too short to fit these two brand new Andersen windows that they had been given they wanted us to make them work typically in the situation that hire a company that cuts foundations for us but they're costly and they charge sixteen hundred bucks a day day rate so we'd probably use a gas cut-off saw right but the house was occupied they had small kids and we thought we want to avoid the exhaust fumes so we settled on using our Husqvarna 19 inch cordless cut-off saw we used these on our head-to-head that we recently did if you haven't seen that head-to-head you've got to check it out this saw runs on batteries does not pollute with fumes and be because the saw only has a three inch depth of cut we knew that we would have to cut on both sides of this wall to make it work so we were going to install these two windows we wanted to pretty much put them side-by-side with a 2x4 between them for a nailer for trim and that gives us just a little bit of trim but it's also good for our nailing flange the windows would be installed within a frame of 2 by 8 pressure treated lumber because we wanted it to span enough of the concrete block to get into some good solid securing you know with tap cons so we determined our rough opening by placing the windows on the floor gave ourselves an inch and a half space between the two when we measured and we measured the width and length we added an inch to the width and a half inch to the length for shimming and plumbing once we had this measurement figured out we needed to figure out our framing measurements to get our total cut so we added 6 inches to the width to accommodate for two two by eights Jack studs on either side and we decided to just cut really low at this mortar joy to make it easy for us to give us enough room for a seven and a quarter inch header on top it worked out perfectly actually so adding these measurements to our rough opening measurements gave us our total concrete block cut and with these total measurements figured out we transferred the measurements onto the concrete wall leveled and plumbed our marks and then we used a permanent marker and the reason why is permanent marker is when you using the cuffs all the water will wash off chalk or pencil lines and stuff and it's darker than a pencil as well once the window is marked out on the inside we used a Makita SDS hammer drill we drill through the lower corners to mark those locations on the outside and then we just transferred those lines onto the exterior of the wall to mark those as well because remember we had to cut on both sides we'd set up a water hose first soft so we do wet cutting operations to keep the dust down as well as a wet/dry vacuum to collect a slurry when cutting a concrete block if you can I always try to cut within the mortar joints if possible and we use the soft first to score the line and get that cut established and then we plunge in and make our three inch deep cuts once complete we use a sledgehammer to break through the concrete blocks at that score line now once you've opened that wall up you'll have a number of partial concrete blocks that it's going to need to either be refilled with mortar or replaced with half blocks so you can repair that opening as required you can use wire mesh in those cavities so that mortar has something to hold on to or in our case we were able to actually put a wood buck right inside the cavity and secure it in place with tapcon screws so this two by six it's pressure treated and it it fills the cavity beautifully so when it's in place and secured our frame could just nail right to it which was perfect and now that worked on one side so we use pressure-treated lumber and we did that in all areas that contacted our concrete and 2 by 8 pressure treated lumber was used and the first piece to be installed is the rough sell so we chiseled as needed we got it level and then we installed our rough sill plate in the opening and the sim plate was fastened to the concrete block with 3-inch tapcon screws you have to use an STS hammer drill obviously we drill right through the wood into the concrete install them we did eventually do a triple 2x6 header above and we did two double 2x8 Jack studs on either side we also measured out the middle and we put a stud in the middle put Vicor all on the bottom sill and wrapped it up and then we installed our window level and plumb nailed them off with 2-inch nails and then taped the nailing flanges with 3m flashing tape that's it it was that easy the next step would be on the inside would insulate the gap between the window frame and the rough opening we haven't done this yet but we would and would use low expanding foam insulation the reason why you use low expanding foam it's it's formulated not to expand excessively and warp the window frame and then lastly wood you know we trim the outside and then when the walls are built on this basement will do you know will tie in the walls to the window frames they'll probably be a deep window jamb or something like that hopefully this video gave you a decent understanding of how to cut a concrete block wall and install a window in it if you enjoyed this video please consider subscribing to the channel or give us a thumbs up a like I'm Rob Robillard we'll see you next time here at concord carpenter

Channel: A Concord Carpenter / ToolBoxBuzz

Views: 132,800

Keywords: diy, how to, step by step, tools, reviews, carpentry, remodel, construction, basement window, egress window, how to install, concrete, cmu, concrete block, how to cut, cutting concrete wall, cutting concrete block, window

Id: BZCDJno7vzE

Length: 5min 44sec (344 seconds)

Published: Fri Dec 20 2019