Joist Reinforcement: How To Strengthen Wood Joists?
The first thing to remember when reinforcing wood joists is that it’s not just about adding weight. You need to add strength too. A good way to think of it is if you were going to build a house, you would want the walls and roofing materials all reinforced together so they could withstand the most damage without breaking down completely.
You will also want to make sure your joists are strong enough to support the weight of the structure. If they aren’t, then you may have problems later. For example, if you’re building a home with no foundation and don’t have any other structural supports such as beams or columns, then there isn’t much point in reinforcing the wood joists at all because they won’t hold up under their own weight anyway.
If you’re doing it right, the wood joists should be able to take the stress of being supported by the rest of the structure. They shouldn’t sag or even bend in certain places, but they shouldn’t break either.
It’s also important to note that you don’t need to use screws or nails. Nails can cause holes in your floor and screws can easily fall through them (or worse).
So what kind of joists do you need to reinforce? Well, there are two types: solid and hollow. Solid joists are those which have a fixed diameter (i.e., they don’t expand or contract) while hollow ones tend to expand and contract over time due to moisture infiltration into them.
Hollow joists tend to be stronger than solid ones since they usually have some sort of shear resistance built in. So the question becomes, how do you go about reinforcing them? The best way is to use these metal plates that you can get at any hardware store that have holes for screws in them. They can be screwed into the top of your floor and into the bottom of your wood joists. This way they’re still secure, but they don’t damage your floor.
This is probably the best way to reinforce wood joists.
One way is to put steel plates on the bottom of them. These plates should be able to hold up a lot of weight even if you are placing all of it on a single joist. They work by providing support to the fixed end of the joist so that the other end doesn’t have to carry as much weight. (This is especially important if the other end has a wall or some other obstruction on it).
You can get these steel plates at any hardware store.
You will also need wood screws and outdoor construction adhesive to hold these steel plates in place. (don’t worry about the adhesive since it’s water soluble and will wash away when you’re done)
The first thing that you want to do is figure out where you want the floor joist to be located since you need to drill pilot holes for your screws into the concrete before you add the plate.
Next, you need to drill holes into the new plate itself so that the wood screws have something to bite into. This is important otherwise the wood screw won’t be able to support any weight.
You then want to place a generous amount of adhesive onto the steel plate and place it against the concrete surface (with the pilot holes that you drilled lined up against them). Now you can screw in your wood screws.
The last thing that you want to do is place a generous amount of adhesive on top of the wood screws and place your flooring onto them. This will help to secure everything in place and will also help prevent squeaks or rattles since the adhesive acts like glue to hold everything together.
You’re done! Now you have a floor that can support weight even if there isn’t a wall on one side of it. This technique is commonly used in basements where the flooring is independent of any walls.
You can also reinforce wall mounted joists (as opposed to free standing ones). The procedure is similar except that you drill through the top of the wall instead. The rest of the steps are exactly the same.
Now your house has a finished look to it and you can move furniture back inside.
There are no real code requirements when it comes to flooring over a crawlspace since the weight that is applied to the floor is relatively little. There is one consideration though and that’s air flow. Many codes state that if you have a crawlspace, then you MUST leave openings at the base of the exterior walls large enough to provide air flow. This is to prevent moisture buildup which can lead to many problems including rot, mold, and other water damage.
If your house is new, then the floor joists are located far enough away from the exterior wall that you will be able to place flooring without breaking up the concrete.
If your house is old, then the floor joists (or sometimes wall studs) are located right up against the exterior wall. In this case, it would be best to leave the concrete intact and not mount anything to the floor. This will prevent moisture from being trapped between the floor and the concrete which could lead to mold and other health concerns.
If you still really want a floor (perhaps to cover up unsightly concrete or as access to your attic), then you will need to break up the concrete and place a layer of plywood over the joists. The plywood must be water resistant or it will soon be covered in moisture. You can then mount your flooring of choice over the plywood. This does increase the work required and substantially increases the cost of putting in a floor since you now need to hire a concrete cutter to remove the slab or do it manually with a sledgehammer and jackhammer.
You can also hire an engineer to consult you on the best way to go about adding a floor (cost: $200-$300). The engineer will take into consideration things like your local climate, house design, etc and make suggestions on the best way to proceed.
If you have any questions at all about putting in floors, I would seek the advice of an engineer before doing anything. Using the floor to gain access to your attic is not a reason to forgo this since safety should be considered before all else.
Even if you do everything right, a floor added to a crawlspace does not mean that moisture won’t build up inside the walls and ceiling. Moisture can still enter and there is nothing keeping it from staying inside the walls. If moisture becomes trapped between the drywall and the frames of the studs, then your house could still suffer from mold and rot problems even with a new floor.
If you are determined to gain access to the attic, then it is strongly recommended that you do so in such a way that you never have to enter the crawlspace. I.e. build a walkway leading up to the attic so that you don’t have to step foot inside.
Remember: A crawlspace is a great place for bugs, rodents, and snakes to live. A dark, silent, damp place where food (you) might pass through. No need to entice them out of their homes into a place where they can be more easily targeted.
If you really want to get rid of them, then you will have to go in. Fortunately, this is easy enough to do. You just have to make sure that you, yourself, aren’t eaten in the process.
Most “pests” will run away when the light is first turned on. Just make sure to aim your can of Raid or other flammable aerosol spray in the direction of said pests before spraying. This will give them a momentary pause to rethink their lives.
Your primary targets should be the brown recluse spiders. They tend to hide under things like cardboard and leaves so be sure to look under those. Also check under items like trash bags, boxes, etc. Shake them out if you have to.
THEY ARE FAST, so don’t rely on just looking. Give everything a good shake.
Spiders tend to hide near the bottom of objects so they can quickly crawl away from perceived threats. Also, they like dark places so shake things that you wouldn’t normally think to shake like an old rusty bucket or wooden log. If something is hollow, it’s a good place to start.
If you manage to get all of them, consider yourself lucky since they are a particularly hard pest to completely eradicate.
Now that you’ve gotten rid of the spiders, let’s take care of the rest of the “normal” pests. These are animals that aren’t as fast and won’t come back once you’ve killed them.
First of all, you need an effective but preferably non-harmful (to people and property) poison. You could go with something like Raid again. It’s effective and requires little effort on your part, but as we’ve seen it is harmful to both people and property.
Hunt around online and you’ll find several recipes for homemade rat poison. Pick one and make a large batch. You will need to apply this in a specific manner–more than just scattering the stuff around the perimeter of your house.
Follow the instructions EXACTLY. Most of these recipes are effective because they contain anticoagulants. This means that while the pests are nibbling on the bait, they are actually eating themselves from the inside out. A nibbled on poisoned piece gets passed around the community before they finally die.
Make sure you apply this to a hard surface such as wood or concrete where the pests will be running around. Applying it to carpet or cloth will just result in it getting kicked all over and making a mess but not actually killing anything.
The best areas to place this are up against the baseboards or anywhere that you’ve seen signs of chewing. Rodents mostly chew at night (of course) so this is when you want to apply it.
Once again, check around online if you don’t trust my tips about where to place the poison and what poison to use.
If you’ve done your job right, by this time next month you should have a significantly reduced rodent population.
The only thing left to do at this point is clean up. This is actually a good thing since it will prepare you for the next part of your plan.
Taking out the trash (literally)
So you’ve gotten rid of the easy prey. You’ve gotten rid of the ambush predators. What’s left? The competition.
The snakes and the big cats have the natural advantages in this habitat. You need to even the odds a bit.
You will be feeding them of course. This is actually pretty easy. The local grocery and convenience stores get shipments every day so just go there when they are receiving deliveries and pick out a couple of the boxes:
Put the box in the back of your car and wait for nightfall. It’s best to do all of this when your family is asleep.
A quick note about the “wild” cats since you may not have ever been around them before:
They are nothing like housecats. They aren’t cuddly and they aren’t pets. While they may play and be affectionate with each other, they are ultimately still predators. They will attack anything they perceive as weaker than themselves including humans.
Even the pet ones that are supposedly domesticated.
So when you are feeding the big cats, never let them corner you and never let them see you as weak or vulnerable. Always be in control of the situation.
For this first trip just take some fish. They like it and its easy to get. Don’t worry about going out too far, you’re just testing the waters so to speak. Go to a different store if the one you picked has too many onlookers.
When you get to the store, wait until the place is empty and start taking fish from the bad as described above.
Take the fish out of the plastic they are in and only take a few. Try not to cause a mess. Then just put the box near the edge of the enclosure where the big cats can easily get to it. Remember, they hunt at night so if you see one in the morning, you’ve done it wrong.
When you’re positive that the cats have had time to eat, leave the store like you normally would.
Leave the same way you came in. If possible, take the same path you did before. Just keep going until you’re out of sight of the store and then head for home.
If there were any problems, they should be taken care of by someone else now. After all, a stray dog or raccoon were the most likely ones to cause issues.
As you get closer to your neighborhood, take the road that goes behind all the stores and leave your car a few blocks away from your house.
Now you just need to do this a few more times and then things will get easier. There are enough cats in that colony that they won’t go hungry for too long and they’ll start wandering a little in search of food. Eventually they’ll be right near your house where you can start feeding them on a more regular schedule.
Once they get used to you and see that you mean them no harm, you can start petting them and such to really break down the barrier. From there it’s just a matter of letting nature take its course.
Once they trust you, they’ll actually let you get close enough to put a leash on them and walk them like a dog. It’s not the best idea, but it’ll keep people from wondering what you’re doing wandering the streets at odd hours.
Once they’re pets, it’s just a matter of keeping them fed. You’ll need to get a job but that can come later. For now, just focus on getting them used to you.
You get to work right away. You head down to the local supermarket. It’s late, so there aren’t many people in the store but there are still plenty of things that could go wrong.
You walk around for a while looking for what you need. There should be some cheap hotdogs in the deli section. Not exactly what the cats are used to eating, but they’ll eat it all the same.
Sources & references used in this article:
- Reinforced wood I-joists with web openings (M Shahnewaz, MS Islam, M Ahmadipour… – Journal of Structural …, 2017 – ascelibrary.org)
- Cold-formed steel reinforcement for improperly cut wood composite I-joists (DP Hindman, JR Loferski – Practice Periodical on Structural Design …, 2008 – ascelibrary.org)
- Steel-wood system (M Leblanc – US Patent 6,167,675, 2001 – Google Patents)
- Steel-wood system (M Leblanc – US Patent 5,809,735, 1998 – Google Patents)