Drill 1-1/2-in. holes anywhere in the web area of engineered I-joists, except within 6 in. of walls and rim joists.

Diamond Drill Bits– This quality carbon steel and diamond tip set is for the big things like copper pipes and steel pipes for gas and water. Large enough to complete the job. Just make sure these bits are not becoming too big for the joist. And be sure to clean out the wood in the bit in between drilling multiple holes.

How to position holes correctly so they don't weaken the joist

The Timber Research and Development Association ( www.trada.co.uk) is a useful source of information regarding the drilling and notching of timber structural elements. Keeping the hole in the middle of the joist evenly distributes the weight of the floor above around it. Wider than a third of the board and the joist’s ability to do that becomes severely compromised. If you have a ¼ inch piece of wire, for instance, by all means, use a ½ inch drill bit so feeding the wire through is easy. However, you certainly do not want to make a 1-inch hole in this situation, regardless of how tall the joist is. The bigger the hole, the less opportunity you have in the future to add more holes should they be required on another project. If you’re already using the FlexVolt platform, adding the bare tool or an extra battery with the kit is definitely the way to go. But if you’re not, Makita sits real pretty in the value category and Milwaukee’s 2 x 9.0 Ah kit gives you a ton of battery capacity for the price. Where DeWalt is going to rise above the other two is with sheer power. If that’s your biggest priority, the DeWalt hole hawg is the way to go.

If this is a joist in the middle of an unfinished basement, chances are high you will easily be able to see on the other side. Before you drill, you notice a wire or pipe. The joist is not maxed out though; there is still plenty of space for the hole you need. Please follow these rules when notching joists. This also applies to wall studs for concealed showers etc… You can notch and bore joists without sacrificing critical strength, but you must follow the rules. The DeWALT 20V MAX* Brushless 7/16″ Stud and Joist Drill is a very specific tool that appeals to particular tradespeople. Because of this, there isn’t a lot of competition. The most comparable model available is Milwaukee’s 18V Hole Hawg Right Angle Drill. It prices similarly, but it does not have safety features like DeWALT’s innovative E-Clutch System®. This safety feature matched with 20V/60V MAX* FLEXVOLT Technology gives you a high-performing, professional-grade drill that is also safer to use. When installing pipework or cabling, floor or ceiling joists may need to be notched or drilled. But this could weaken the floor to such an extent that it becomes structurally unsound.The rim joist ( Fig. B)—the framing member that runs around the perimeter of your house and that the floor joists butt into—often gets riddled with large holes. This space is the logical exit point for dryer and furnace vents, big electrical service wires and fireplace fresh air intakes. Since the rim joist is continuously supported by the walls or foundation it rests on, the strict notching and hole-boring rules don’t apply. Just don’t create a large hole or notch directly under a group of studs that support the end of a beam, or a window or door header above. To understand the forces at work in a joist, particularly the tension and compression forces please see our project that explains how the forces that affect buildings work. Rules for Holes in Joists Alright, so those other options will not do. You still need to drill a hole through your floor joist. That should be perfectly fine, provided there are only one or two other holes already in its vicinity. Specifically, the hole should fall under the following requirements: Keep the measurements the same, if possible. You want to keep the heights exactly the same, especially for water pipes.