The DOs & DON'Ts of DIY Spray Foam Insulation

[@carlafoxworth3501]

Thank you Aaron! I'm a single mom and learning to fix my own issues. So far I'm doing pretty darn good - and enjoying my journey toward taking care of my family myself! I'm definitely teaching my daughters to take care of themselves too. For example, I service my own air conditioner every year and treat it monthly...and just fixed my neighbor's air conditioner when it quit on a scorching SC summer day. I taught both of my girls when they were in middle school how to fix running toilets. Videos like yours are so helpful, so I want to thank you for your help and guidance. (I do know, however, when something is over my head and when to call in a professional.) This being said I want to leave a note to Dads: Please teach your daughters everything you know so that they can take care of themselves when they reach adulthood!! They will be better and stronger women because of it! And they will always remember that Dad loved them enough to teach them. As for the LocTite, I just purchased some to hopefully deal with a carpenter bee problem. They come every year and set up under the railing on my porch. I've tried everything the experts say: insecticides, borer bee traps, citrus soap... but nothing works. They still show up every year and leave a huge mess on the porch. So, today I'm getting serious - and am going to try spraying Loctite foam under the rails and hopefully take care of this issue once and for all. I'll let you know if it works! If not I may be tuning back in for help with this. Thanks Again! Oh, one more thing I'll pass on... the air conditioner pan was getting rusty and on the verge of rusting out holes. So I got some FlexSeal and painted the bottom of the pan. Worked like a charm. No more rust. I also decided to paint the bottom of my kitchen and bathroom sink cabinets with FlexSeal to protect the wood flooring from the occasional leaks. Hope someone finds that helpful! CJ

[@bot5245-0]

GO GIRL! KEEP IT UP. I DO THE SAME. We are strong.

[@bot5245-0]

Just lean on the Lord Jesus and He will show you the way.

[@veronicapadovani4243]

Great to hear! Good for you and your girls ❤

[@MrFixItDIY]

You're awesome! Keep up the great work!

[@mythreeboys6623]

◾️I absolutely did find your comment helpful. Great idea spraying FlexSeal under the sinks! I’m 57yrs.old. My Son’s are grown & out of the house. Taking care of my own issues also. I’ve been stressing about what to do about under the sink. Really great idea! Thank you very much. ☮️

[@davidcarvolth7685]

For rats and mice use stainless steel wool, as rats can't stand chewing it. (Its an old pest controllers method)

[@lolafalana6960]

Don't forget the nails in the steel wool for NYC rats. They're onto the steel wool trick 🤣

[@DARWINZOO]

Broken glass in quikcrete

[@marklittler784]

@@lolafalana6960 Yeah they're getting more crafty.

[@commonsense5489]

That’s funny I’m from inner city Washington, D.C. south east, Barry farms. Rats chew through pipes there with a wall thicker than 1/4 in steel🧐 city’s all over the world have rats that eat through walls of concrete, thick galvanized and stainless steel pipes all the way to standard dry wall. The only “rat” steel wool will “stop” is the common pack rat🧐 which is a mouse and not actually a rat.

[@sdot5389]

Mice chewed right through steel wool in my house.

[@larrybruce4856]

I learned a "don't" when I bought a Condo in 1995. Although the Condo was only 5 years old, It had low grade Hotpoint appliances. The dishwasher was noisy everytime I used it. I sprayed a little foam insulation in the door, thinking the insulation will absorb sound and quiet things down. After spraying the foam in the door, I didn't realize heat from the dishwasher would continue to cause expansion of the foam . After two uses, the foam continued to expand and the front door panel started to bulge. As funny as that was, the timer eventually got clogged with the expanding foam and the dishwasher became useless. I was going to replace the appliances anyway but didn't realize it would be this soon. I learned my lesson and now pay more attention to the "Do's and Don'ts of spray foam. Thanks for the tips on Spray Foam Do's and Don'ts ! ! !

[@marklittler784]

I love it when they put picture examples of where it can be usefully applied on the can.

[@TaskForceBorderLine]

I use drinking straws from the grocery store and save the ones that come with the can. they are slightly smaller in diameter than the threaded nozzle but stretch and screw down tightly. super cheap and effective. I use these if I know i am not going to use the entire can.

[@dandiego7298]

I was a little wary when I saw you were sponsored or paid by Loctite. However, after watching the video, I could see that you really know what you’re talking about and you gave some great points for and against the use of spray foam. Excellent video.

[@dallasvanwyk]

Great video. It pains me to see how much half-assery goes into so many home repairs, and I'm grateful for you pointing it out

[@hipairbrush1053]

Every single product I've ever used by Loctite has been absolutely incredible. I'm not a paid guy for this and I don't have any contact directly or indirectly with loctite. I don't even know where they are located I absolutely love their 3x construction adhesive and fast grab (I used them together)....just terrific. Their thread lockers have always kicked butt ....

[@Rearmostbean]

Same, locktite is great

[@wtfcookie2000]

I am filling in a gap in the corner of my kitchen next to the window. When they did a remodel for some reason they did not seal the corner. I have been fighting little ants in Spring time. Now I know from watching this video I can safely use spray foam for this project. I am also going to seal around the gas pipe connection in the floor. I did hit the like button and I subscribed. Thanks!

[@notyetskeletal4809]

There were so many warning of its toxicity on the can. I imagined this video may have touched on those. Anyhow...nice video and it gave me some tips.

[@siezethebidet]

Thanks. Very useful info. Plus good production. You didn't run some distracting music or sound over your speaking and the visuals were perfect for what you were saying at any moment.

[@FESTIVE1000]

Your video was straightforward and easy to understand. I feel more confident about filling in cracks around my door.

[@dwallce1]

When I have leftover spray foam in a can, I spread out a large piece of heavy plastic and discharge small balls of the foam(golf ball sized) to be used as packing material.

[@rumandredbull100]

Thank you very much. Straightforward and saves a lot of us a lot of money.

[@joshuamoore24_7]

Using dry wall mud and dry wall tape after wetting where possible and meta caulk also is a great idea. For cement the cement epoxy as a filler and epoxy paints or sealer for sealing the cement and other masonry. For red brick use mortar and the epoxy sealer rated for masonry.

[@ksnax]

Trimming the straws into smaller sections before use is another option for later.

[@bradsanders407]

I've never ever had one work again after the initial 1st hour after popping the cherry. That's with no straw.

[@joshuamoore24_7]

I have seen on new homes I was working on they where using cellulose blown in insulation that is shredded newspaper mixed with cement , boric acid, starch, fire retardant, and water. When it dries it's like a layer of cement. It sticks to the surfaces it's sprayed on and can even be sprayed and stick onto the plywood on top of the roofing trusses.

[@sabrinagee-shin6616]

SUPER helpful. I was using my first can and my husband got excited about all the potential uses. Turns out you debunked all his ideas. Thank God for your advice, I'm not letting him near it!

[@frankcorral4981]

Excellent info from your experience in this work. Doing the work right and not by short cuts or "hacks". The do's and dont's very helpful. Thank you.👍

[@RationalSaneThinker]

What the difference between the normal foam and the foam for larger 3" gaps? I know that the latter expands more, but is there a difference chemically and structurally? Can I use the 3" foam for smaller gaps as well? Or would the increased expansion actually force the small crack wider? Thanks for any info.

[@rgcountdown]

Looking to temporarily insulate the gaps in a portable AC vent in my window. Is spray foam too durable to remove later? Should I use something like flex tape instead?

[@LaurelMartinson]

Thanks for being so smart and experienced. This video was GREAT!

[@brittandjosh]

Well this was what we were looking for. Thanks for the info!

[@MrFixItDIY]

Glad it could be helpful!

[@blabbergasted4380]

Gr8 video! Pacing makes it painless.

[@DCherbonnier]

Very good presentation. It didn't have the application /i was looking for but the information it did have made it well worth watching and remembering.

[@alltheboost801]

Can this be used around the water pipes inside the home. In my house around the shower head pipe, under a sink and pipe coming out of the wall to the toilet there is little gaps. Just wondering if it’s safe to use in all those areas.

[@kari-karislinedancing6146]

Excellent and incredibly packed and informative video - thank you!

[@nowucit6346]

Excellent video! Great dos and don'ts tips.

[@TetsusaigaDrgn]

Great video. I know you said not to use spray foam for foundation cracks. But do you recommend using spray foam instead of backer rod and then using sika self leveling sealant to patch exterior cracks where the siding meets the concrete walkway?

[@bradsanders407]

Hell no. Use backer rod dude. I'm a journeyman masonry restoration worker in the bricklayer and allied craftsman union. If you are worried about the sl running out through gaps use regular caulking to fill any such gaps that backer for whatever reason cant. Then back it and shoot it.

[@binu1547]

Hi, Thanks for a great video. I need to fill in a hole identified my a energy home assessment within my boiler room. Due to fire warnings on foams, I am unclear if loctite products would be something I should use. What would you recommend?

[@6636860]

How about supplying the link where a person can get extra straws? Good video!😀

[@nathannagy1499]

What would you recommend for a finished basement ceiling? Their is a drop ceiling, but some areas of the floor on the main level above the unfinished area(s) are quite cold.

[@MrFixItDIY]

I would use batt insulation between the joists.Spray foam should only be used for small areas.

[@wowfreak982]

I'm remodeling/rebuilding a single wide mobile home. The owner is planning on using spray foam insulation to insulate the entire house. Bottom up. After putting in the new plumbing and such going underneath and foaming the bottom. What are your thoughts

[@npzninja]

I'm building outriggers for my kayak, and someone said I should use "spray foam" to reinforce their strength, is this the stuff they were talking about? or will it make the pvc crack more easily?

[@TheNewenglandboys]

Just an fyi: after using the straw, take it off and spray wd40 through it to clean it out. Also spray it in the top spout where the straw connects. Next time you need to use that can, you’re all set.

[@fher3786]

I have a wooden balcony right over our front entrance and when it rains water just goes all over the place , could this product be good to fill in the gaps on the balcony in order to stop water from coming down right over the front door ??

[@gettinreal7627]

Good video, BUT as HVAC installer, salesman and duct design and airflow specialist for a total of 30 years, I have learned one thing about complete sealing every crack in your home. It is a bad idea. The intention is to seal every crack to stop outside air infiltration, heat loss and heat gain. While that is a good idea on paper, it is a bad idea for our health. It can create what is called a sick home. Outside air is much healthier than inside air, regardless of the amount of infiltration you have in your home, but no infiltration at all is asking for trouble. You actually want some infiltration especially in a new home that has multiple flora carbons and VOCs that can be dangerous to our respiratory system as well as other reactions. In an attempt to make new homes more energy efficient, they construct them sealing attics, basements and crawlspaces with foam, but this only increases the risk. Some of these are so corrosive they will be drawn into your HVAC system through the return and can corrode the indoor evaporator coil and other metals in your system, so you can imagine what they do to your lungs. This is much worse in a manufactured home because of all the synthetic materials used in them. An older home, especially one made primarily of wood, is much better for your health. In the end, you need some infiltration in your home and a regular airing-out.

[@naz220]

A fresh air intake device needs to be installed on all tightly built homes!

[@ricks1231]

ERV’s are the solution.

[@janetpattison8474]

Thanks!

[@nicksutton2964]

Thank you so much! As a complete newbie to this wondrous foam stuff I was wondering how to clean the tubing before the foam sets. It was your last few sentences that told me! Fortunately I had some lovely stinky acetone handy and managed to save the tube for another day. Also I now know that I can get some more tubes as well. You may be wondering why I didn't read the instructions on the can. Well I am in Japan and I cannot read Japanese sufficiently well, so your video was really helpful. Thanks again. Liked subscribed.

[@michealterhune1200]

Okay thanks for this video now i have a shed that leaks around the floor area when it floods looing to seal waterprrof and insulation to keep the heat out. Do i use a membrane to water proof inter wall or seal then use membrane

[@Aarzak]

Can you use spray foam during winter?

[@christianclough6247]

Hi, iv got a problem with silverfish in my home. They are partly getting in through gaps between floors and skirting boards. Can i use this stuff to fill the gaps in?

[@PrincessBella22]

Is it ok to use it behind the dryer??

[@bridgettegalvin3752]

Loved ur video...but can I use it near heat...I have base board heat & mice r always getting in thru there...plz lmk thnx

[@TownGirl04]

No. I have a heater in a condo. They did not finish underneath it. There is two inch between end of heater to floor. Floor has not caulk, or quarter round, or anything. Can I spray there, instead of caulk it (cuz you can’t quite reach caulk gun in there) .. ? The only thing I cannot find online is a picture of how much it expands and if I can use it there. (some sort of slant/fin heater for gas heating)

[@tinalundy7858]

So question I have yellow jackets I my garage going in a Crack in the concrete can I spray foam and it seals them in the ground???

[@Lutzboater]

Great information, thanks for your take on spray foam.

[@MrFixItDIY]

Thanks for watching!

[@samanthapeck8395]

I just used some to try to keep an exterior light from continuing to fall out. I'm hoping the tite foam stuff will lock it in place.

[@sicsemperevellomortemtyran3193]

Do crawlspace/basements have to vent? I have a vent that goes to the outside, I'd rather seal it up. Thoughts?

[@mysticmek93]

Wondered about using this instead of fitting a Styrafoam cooler liner inside a plant pot to make a makeshift hidden insulated cat shelter.

[@asdfsfasdfasd]

Can this spray foam be used on car's noise cancelation?

[@Steelrain-zg7fx]

How about sealing areas where bats can get from the attic to the living room via gaps in trim and gap above a dual sliding wooden door in my living room. Bat person recommended a sealant of some type?

[@diatonicdelirium1743]

After use set the can upright, let it settle for a minute, and blow the foam remains out of the pistol and straw. Remember: short controlled bursts, as you would use on any alien.

[@asantos859]

Could I use this in drywall to insulate drain pipes?

[@avinashkrishnappa1115]

Hi Aaron. Thanks for the great tips about foam insulation. My main concern is that I've had issues with blinds falling off due to poor structural integrity in the ceiling of the window. Unfortunately the gap between the ceiling and the brick wall is only about 2-3 cm. My query is, can I use the foam to fill up the space, then use filler to close the gap and then create a new hole for putting up the blinds again?

[@bradsanders407]

Your question is rather confusing but if you are asking if the spray foam will support the blinds the answer is no. If your wall won't support blinds then you have an incredibly bad situation. Your house should be abandoned and torn down. It's not safe to be in. That being said, you then went on to talk about brick. Is the brick on the inside? If so and they are secure, that is what you need to be attaching the blinds to. Assuming they are real and not imitation. This can be done only with a hammer drill and a masonry drill bit and tapcons. Figure out where the holes should go and mark them with a marker. Take the masonry bit and drill in as deep as your tapcons are long. 1 and half inch tapcons are plenty long enough for holding blinds. There's your new holes the tapcons work just like any other screw but they are hard to turn so use the drill for those as well. If it's drywall that your screws keep falling out of then you aren't hitting the studs with the screws. If there are no studs I would use toggle bolts. They are far superior to any insert style anchor for drywall. If you are doing any of these already and the wall won't support blinds then you have major issues. Note that if you are trying to go through the top of the window and have used those holes up and are now hitting brick, then again, use tapcons right where the old holes are. This may require longer tapcons depending on how far in the wall they have to go til they hit the brick. It is important to determine if it is metal or brick as it should have a metal lintel. If that's the case go in from the sides with the tapcons. Once you do all that, then fill any gaps with spray foam. Hope that makes sense P.s. with the tapcons it is imperative you use the correct size drill bit which the tapcon package will say the size you need.

[@harreetteB477]

Very efficient, helpful, valuable information! Thank you!

[@rustixpanda1921]

Question so I have a small ac in my room and it keeps leaking from the bottom and the bottom of it there is like a line where I'm guessing the water is coming out from can I use the foam to stop it from leaking from my room

[@diaperdood1]

Is it ok to apply spray foam insulation when the attic is 110 degrees? Will it fully cure? Or will it off gas forever?

[@FirstnameLastname-qc3xx]

I have a small attic access door that I don’t really need to have open, it’s full of blown in insulation so I can’t really go in it. Figured it would be easier to either use spray foam or maybe the expandable stripping. I’d rather be able to easily cut it open and be able to use the door if needed for leaks.

[@vonbeats2135]

Hey was this of using this for the basement door way. Water is coming in through the walkway without the door opening.

[@zack2chat812]

Furnace in attic, foam on air conditioning unit.. Good or bad?

[@bhatkat]

You can clean out the straws by inserting a bicycle spoke in them before curing, screws in the can openings. And he forgot how to use it for weather sealing doors. Yes, you read that right, secret is to use cling wrap as a release film, first tape a strip of cereal carton cardboard on the edge of the door as a spacer, mist it with water to help the cling wrap adhere. Then with the door closed you fill the crack with the foam and let it cure. It will be difficult to open the first time but then you will have a crack up the 3/4" filled and a good seal. Paint as you choose, great for a temporary fix or low end housing.

[@juliekoester7776]

Great tutorial! Thank you! P. S. I love your shirt! 😂 👍

[@hellrazor117]

Which foam is best if i want to hide something under it?

[@maxzarmar8908]

Can you use Loctite Tite Foam Gaps and Crak around HVAC vents?

[@guo-yinxu4536]

Very helpful examples!

[@oldfashionedmusic]

is ok to use GAPS N CRACKS spray foam as insulation say after window casing rebuild due to leaky window ac repair, to bugproof my manufactured home because i will be having OTA ANTENNA ALSO GOING THRU THE WALL. i wanna stop bugs n drafts from getting in, BUT TO BE CLEAR NOT JUST ONE SMALL SPOT THE WHOLE WINDOW CASING WHICH ABOUT 12 INCHES HIGH BY 52 WIDE?

[@virginiatyce8893]

Hello, young man, my name is Ms. Virginia. I live in an 1880 farm house I bought 5 years ago and have put almost all my savings into it just as Covid 19 hit. Prices double and then tripled. The contractor I hired; well, I can say they got paid 3x over at the time. I was trying my best to do work myself when I was diagnosed with Stage 3 Non- Hodgkins lymphoma . Question = now that I'm better I find CORNERS were cut!!! My kitchen is an outside wall; the cabinets and drawers floor feel like there's nothing there!! No wall at all. I know they should have put insulation in the walls because they blown that in!! But I do know that the walls have a divider ? Board in-between the 2x4 centers of that makes sense to you. Apologies for going on.. Truly would appreciate your thoughts or advice. May GOD continue to bless you and your family 😊amen

[@jaredharris1970]

My question is could I use spray foam around radiator pipes inside house I noticed one day I felt a draft around radiator pipe where there is a gap

[@zacd7094]

My house is 1900 square foot living and has some moderately tall ceilings. I was charged almost 9k. They sprayed the attic under the roof and all of the walls that are against the outside elements for 9k they didn’t do any interior walls like bedroom walls and stuff. Is that Norma??

[@adeletanner2262]

I recently purchased a can of the locktite window and door foam to replace the fiberglass insulation originally stuffed around an Anderson sliding glass door in my home. It didn't take long, but my previously perfectly functioning sliding glass door would not open anymore, as the loctite product had bowed the door framing. And when I say it would not open, I mean it would not open! It took a lot of time and effort, using hacksaw blades and other tools to dig and remove the locktite foam from the 2x6 framing, but after its removal the door functioned perfectly again. Further investigation revealed the the locktite product also contained fewer ounces of product in its can than Great Stuff contained, at the same price. I applied the Great Stuff and the door functioned perfectly. YMMV, but IMO, Locktite window & door foam is overpriced junk...

[@curious_foxx2450]

Can I use this foam spray for insulation for my 97’ F350 van?

[@kel06901]

Can you use spray foam to fill in gaps in a galvanise shed? At the bottom where the shed comes down past the concrete slab. Can I use it there to prevent water getting in?

[@brucegordon3566]

Will it work on top of gravel

[@tombowler6458]

Great tips, thanks for posting. Question for you: Can spray foam insulation be used to plug hole (4" diameter) in the wall left over from old vented tumble dryers no longer in use, or should I seek alternative solution?

[@rosstee]

Did you go ahead in the end, as your comment describes what I'm planning to use spray foam for? I believe it should work fine as long as the exterior side is sealed/painted after the foam has cured/been trimmed, to protect from the weather?

[@stevenlawrence5733]

What spray foam works around hot copper heating pipes to plug the wall holes around the pipe???

[@TheMrFlyBoy18]

Can this be used to insulate a dog house I will build?

[@mrwaynebangsil2002]

can i use this for balloons? for them not to deflate forever? im serious.. need to know so i can use this to my 1988 turtle blimp playmates toy..

[@miniioe]

Can it soundproof?

[@freaklatino13]

can i use this near radiator pipes? there is a gap next to my radiator pipe that i want to fill but im afraid its gonna catch on fire if it gets too hot

[@PatriotPerson11]

We had a faulty valve on frig cause leak which damaged cabinets & drywall behind the frig into our pantry. About 3 feet high of drywall by 20 ft of drywall was removed along with the spray insulation foam. Is the aerosol can foam ok to use to refill this area before installing drywall?

[@PeteBaldwin]

Thanks - I’ve got a gap under a window I’m trying to fill but there’s a uPVC cill that overhangs and then comes down a 90 degrees so I can’t get to the gap in a straight line. Are you able to bend the straws at all or is there a better solution out there? I e had a look but can’t find anything…. Any help would be massively appreciated!

[@jlucche]

So in my Man. Door into my garage on the side of the house there is a visible gap under the baseplate of the door jam. Would spray foam be good to use? Also I started noticing a puddle in my basement near where the entrance would be. So you think that since it is not sealed up it it causeing water to leak?

[@RestoreITdontJunkIT]

Great video, I find myself just buying the spray foam with the pest block added. Whatever brand with the best price n reviews.

[@farhanullahbaig9910]

Can I use it to prevent pipes from freezing?

[@RosaRodriguez-me2zd]

Can this product be use under countertop

[@12vLife]

If I use this stuff to sandwich corrugated polycarbonate roof panels cross sectional in a matrix and then fill the edges solid what kind of adhesion and dilapidation can I expect in the Florida Sun, wind and rain over time?

[@hudatva]

Thanks brother.. that was very nice

[@Tadena22]

I have problems with my spray foam that it'll shrink in just a few days and the gaps are visible. What maybe the reason behind it?

[@Phyllyps-Levine]

Does anyone know how many square feet a 12 ounce can will expand to?

[@galkawarrior]

Can I use spray foam in my hallow door to make it more sound proof?

[@dlsamson]

I have a question about spray foam usage. I have a 1790s house - nice thick lath & plaster walls. However, my kitchen was added in later years & my heat runs ~5 as much in the kitchen zone as elsewhere. The kitchen is also exposed on 3 sides with four windows. The walls have loose fiberglass insulation (almost certainly settled at bottom) & are noticeably cold to the touch. I'm getting ready to remove wallpaper & paint the kitchen so patching holes isn't a problem. Would it be an acceptable solution to drill small holes into each stud space (perhaps at 3', 6' & ceiling) & inject expanding foam on top of the loose fiberglass to increase the R value?

[@purplecolors4121]

I did this to my 1940s home but found the two previous owners were cheap and wanted a quick buck - turns out I have exterior walls made up of drywall-studs-composite siding. Absolutely nothing else. No plastic barrier, no structural plywood/OSB, no insulation, NADA. After spraying an entire can into a spot to fill, my siding popped out and I could see daylight through my very very tiny hole I installed. TLDR - ensure you have a plywood/OSB barrier before applying spray foam into exterior walls. 😅

[@paulwizal23d89]

How do I stop from all the dry gas air bubbles in foam after it drys

[@georgemathew1155]

Very informative. Thank you very good.

[@dachicagoan8185]

You didn't mention that it wasnt safe to use it in circuit breakers. It doesn't say anything about that in the can either. So i used a little bit there to seal air gaps in some openings for wire bundles.

[@graciecai7131]

Love your video! so informative! I find gaps inside the radiator in my apartment. Will spray foam be ok to seal the crack and the hole around the steam heat pipe?

[@jb888888888]

At Home Depot an employee told me that they don't sell replacement straws even though it would be very useful. And by "they" she didn't mean HD she meant the spray foam companies. She said to only get the kind that says "reuse it" unless you know you're going to use the whole can at once.

[@diatonicdelirium1743]

Makes sens from their point of view: supporting reuse puts some liability on them, they'd rather you buy a new can and not sue them!

[@GrandmasterofWin]

Gotta love hearing what you've already done is a big no-no... I took a can of great stuff and sprayed it into the gap between a cinder block wall and sidewalk, mostly filling large cavities in the wall, then went back and sealed with a concrete/silicon caulk for a watertight seal. Too late to change anything now. The building owner refuses to take responsibility for his building and says it's fine despite the raise sidewalk allowing water to pour into the building and saturate my equipment.

[@Handheldsounds]

Can I use spray foam to fill a gap in a bathroom exhaust fan between the enclosure and the ceiling drywall?

[@zeeman9145]

my wooden floor is sagging when I walk between supporting 2 x 4s that are laid on the concrete approximately 3 feet apart. I do not know the proper name for those supports so I will refer to them as beams. simply, there are not enough of support beams that are laying on concrete floor, I think they should have laid those supports every foot or so to give it more stability, then put the wooden floor on it. This is a cottage so previous owner did not invest lots of money in quality work. So, because sub-floor is poorly constructed there is a quite of a sag when you step between sub-floor beams, so my question is - can I inject the spray foam between existing floorboards and concrete surface by drilling through the floor boards in order to help stiffen the floor? I am thinking that maybe drilling the holes in the floor on every couple of feet between the supporting beams and injecting the foam will stiffen the floor, then I would lay over this a new hardwood floor. any pros or cons?

[@geewilliams2178]

I want to use spray foam to fill the void in between the stud walls between bedrooms in my home (im in the UK) I am thinking of drilling lots of holes and starting any the bottom. What do you think?

[@ChristianWagner888]

Did you ever try that? I think it would take too many cans for a whole wall, because I tried it for 2 m width by 60 cm height, and it was not very cost effective. T here are companies that use large volumes of polyurethane spray foam for roof insulation with special applicators. I think something like that would be more suitable.