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Got cellulose insulation, how to fix the interior holes?

AlanB4 | Posted in Green Building Techniques on

They drilled two holes and loose filled it (i know, it should be dense packed). The holes are 2 inches wide, and plugged with styrofoam discs about 1in thick. Some are reasonably tight, some are loose. What is a good way to fix this, if i drywall compound and paint many of these will move over time. I was thinking of using a few cans of spray foam, cutting flush with a painting razor and painting. Would this work well, or do i need to sand and plaster before painting or is there a better way?

Also i would like to dense pack someday, it would be nice to reuse the drilled holes, would a new hole be wider then 2 in. I have no basement headers, the cellulose goes to the bottom of the wood framing in the basement (balloon framing), i could conceivably remove those panels (screwed in), use something temporarily, let them dense pack up to the base of the attic (there are top plates) and replace (and caulk for air tightness).
Thanks in advance for your advice

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  1. GBA Editor
    Martin Holladay | | #1

    Am I missing something, or are you simply asking, "How do I patch drywall?"

    If that's all you are asking, you'll find lots of resources on the Fine Homebuilding web site. Here are some links to get you started:

    California Drywall Patch

    Patching drywall

    Repair a hole in drywall

    There's a Better Way: Large Drywall Patch

    Nifty Drywall Patch

  2. AlanB4 | | #2

    I forgot to mention its plaster/lath/plaster/1.5in thick barnboard

  3. GBA Editor
    Martin Holladay | | #3

    Believe it or not, you can easily find answers to home-repair questions on the Fine Homebuilding site by using the site's search box. Here you go:

    Repairing plaster walls

    Plaster patch

    A New Way to Repair Old Plaster

  4. Expert Member
    Dana Dorsett | | #4

    For plaster/drywall cellulose blowing holes they should have drilled it with a hole saw. Using the same sized hole saw make some plugs with blue-board, and carefully caulk them in place recessed ~1/8" from the surface, which will allow you to fill it out with plaster of Paris (not drywall mud.)

  5. AlanB4 | | #5

    They did drill it with a hole saw (they left one of the worn bits behind), but blueboard didn't come up on a quick google search, unless you meant bluwood.
    Also what kind of caulking, an adhesive like PL premium or silicone caulking like a shower or window?

  6. kshenefiel | | #6

    Alan , some time ago I was faced with patching dozens of 1 inch holes in plaster walls after blowing cellulose in from the inside. I pushed the cellulose back behind the lath; moistened and cleaned the holes with a wet rag then completely filled the holes with base coat plaster(actually a mix of veneer plaster and sand). With little practice plastering holes goes nearly as fast as putting nail holes or drywall screw heads. The thin coat of plaster that gets smeared on the face of the wall doesn’t stick or set up proper and can be wiped off after the plaster in the holes has set Before painting I touched up the rough surface with a little joint compound for an invisible repair. (the same process worked just as well in a room that was sheet rocked).
    A 2 inch hole is still small enough to patch without special lath or backing if you put in a good ¾ inch layer of plaster. I’d just push the foam plugs back to give an inch deep hole to fill. Wall plaster is different than plaster of paris it contains hydrated lime which improves workability and slows the setting. If you haven't worked with plaster before mix small batches till you get the hang of it.

  7. Expert Member

    Alan, Blueboard is the sheet backer product you use under plaster skim coats. You could say it replaced lath. It's a lot like drywall.

  8. AlanB4 | | #8

    Kevin said "Wall plaster is different than plaster of paris", when i search home depot's canadian website for plaster i get plaster of paris, is there something else i should search for to find the wall plaster?

  9. Dana1 | | #9

    For quick repairs plaster of Paris is the right stuff. Yes, it is different from plasters, and it sets up fairly quickly, which is what you want for patching, mixing it in small batches. It sets up harder than drywall mud. You'd never plaster a whole wall with it due to the quick setting, but unlike lime plasters which need days to fully cure, you can paint over it within just a few hours.

  10. emeliza | | #10

    I also drilled holes in lath and plaster walls in an old 1830 farmhouse and then blew in cellulose. The easiest way I found to patch the holes was to use canned foam (inserting the wand in the tightly packed cellulose, letting it harden and then cutting the bloops with a serrated knife. I created a little indentation with the knife and then covered the holes with drywall mud. If you have to make the patch bigger than the area of the hole, that's okay. Some of the rooms I was taping hairline cracks with webbing and skim coating the entire wall, some rooms just patching holes feathering out to the edge. After sanding and smoothing the wall surface, I primed it, then painted with my chosen wall color. Easy peasy but time consuming and I can't tell where the holes were now that all is said and done. My walls aren't perfect, but then again, it's an old farm house, imperfection rules!

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