Replies

1. 
   MikeHennessy | Sep 08, 2008 02:24am | #1

   Is the plaster in good shape? If so, keep it. It's way better than plasterboard and cheaper to maintain in the long run since it doesn't ding as easily. You don't say what your construction is, but if you have stud construction behind it, you can get celulose blown in for less $$$ than ripping out the plaster, insulating and re-doing the walls.

   Mike Hennessy
   Pittsburgh, PA

2. 
   MSA1 | Sep 08, 2008 04:13am | #2

   There's no way in the world I would apply rigid ins then drywall ovfer existing walls.

   Some might, but it just seems like more trouble than its worth. You have to strip all the existing moulding then build out all your openings when your done applying your insulation band-aid.

   I dont know you and I dont mean to offend you but it really drives me crazy when I speak with other landlords and see what they market for people to live in.

   I refuse to rent anything I wouldnt put my family in. I have 6 units and we renovated all of them before marketing.

   Sorry if it sounds like i'm calling you cheap (I dont mean to) it just sounds like hack type work. I may be wrong though.  

    

   Family.....They're always there when they need you.

1. 
   popawheelie | Sep 08, 2008 04:26am | #3

   I have walls that I was thinking of insulating that way. You call'n me cheap!

   Just kidding. My exterior walls are brick with 3/4" furring strips, then a 1/2" fiber board(insulation), then drywall.

1. 
   MSA1 | Sep 08, 2008 04:35am | #4

   I just have a problem with layer after of layer of wall. It just seems like poor practice to me.

   As I said I may be wrong, but its not something I would consider to be a good quality job. 

   Family.....They're always there when they need you.

1. 
   popawheelie | Sep 08, 2008 04:43am | #6

   I'm just mess'n with you. But I am thinking about it. Maybe I'm just lazy.

2. 
   Clewless1 | Sep 08, 2008 03:54pm | #14

   But there is a time and place for just about everything and while some aspects of it may seem 'cheap', it does have its merits. Pay your money and take your choice I say. Way ALL of your options and then make an informed decision. I don't begrudge your opinion at all ... totally respect it.

1. 
   MSA1 | Sep 09, 2008 03:52am | #26

   All I know, is that I was born with a whole a s s therefore I never use only half of it.

   If you do, it tends to wear unevenly, then you start to walk funny. 

   Family.....They're always there when they need you.

2. 
   Clewless1 | Sep 09, 2008 05:22am | #27

   I hear ya ...

2. 
   sisyphus | Sep 08, 2008 04:48am | #7

   The other problem with shooting rigid insulation over the existing wall is that you end up with a cavity that will convect air and in a multifloored building may leak in and out of the interior ceiling space...UGH!

1. 
   MSA1 | Sep 08, 2008 04:53am | #8

   Didnt even consider that. I was just concerned with the logistical nightmare of extending electrical boxes and building out every other opening. 

   Family.....They're always there when they need you.

3. 
   sisyphus | Sep 08, 2008 04:43am | #5

   You could do either, although 2X8 sheets might be better. Much depends on how the wall is built.

    How old is the wiring? Now would be a good time to address any electrical issues.

   Assuming that there is a 2X4 wall behind the plaster and lath then ripping it out would be my preference. This would enable you to rewire and insulate most efficiently. The downside is the huge mess and added time. Sometimes plaster and lath is on masonry (typically brick) in which case there is less to be gained by ripping it out (a slightly larger room and a cleaner structure) unless you want to leave the brick exposed. 

   As mentioned by a previous poster you could also insulate by blowing cellulose into the existing cavity. This is the fastest and least expensive route but will probably give you poorer insulation and may cause problems if you have antique Knob and Tube wiring. Never the less the cost savings with this approach may justify the reduced benefits that result.

   
   

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   Edited 9/7/2008 9:52 pm ET by sisyphus

1. 
   Shep | Sep 08, 2008 05:16am | #10

   In a house old enough to have lath and plaster, there's a good chance that its balloon framed.

   If so, its pretty easy to pull new wireing without stripping the walls.

   I did exactly that in my own house. Then blew in the insulation. It was cheaper doing it that way, even with paying the sparkies for old-work boxes.

1. 
   sisyphus | Sep 08, 2008 10:43pm | #20

   I think you are right on both counts. I would expect it to be balloon framed (hence my observation about air leakage) and it would almost certainly be cheaper to blow in insulation. New drywall over existing plaster will, of course, cover any electrician mess and provide a barrier to air flow. It is a judgement call whether or not the cheaper way is what one wants to follow.

1. 
   Shep | Sep 09, 2008 12:35am | #23

   The big thing I learned about blown in insulation is...

   make sure the bays in the attic, and particularly in the basement, are sealed. Or plan on spending some time cleaning up the insulation that escapes .

1. 
   sisyphus | Sep 09, 2008 12:44am | #24

   I remember cellulose stalagmites in the crawlspace on one job.

2. 
   Clewless1 | Sep 09, 2008 03:30am | #25

   I did that once. Merrily filling my walls up ... no problem. This one cavity, though didn't seem to fill up very fast (it only takes a minute). Puzzled, I shut off the hopper/hose ... then a light came on. Went to the basement ... there was a hole near the 'rim joist' ... I had cellulose up to the top of my furnace!! I laughed so hard ... no real big deal, but it was a mess.

   Underscores the importance to study your situation carefully lest you run into multiple 'never thought of that'. Almost act it out on site to ensure you are getting it. Can save you some heartache.

   Edited 9/8/2008 8:30 pm ET by Clewless1

4. 
   Waters | Sep 08, 2008 05:16am | #9

   Blow in.

   They can accomplish this from inside or out.

    

5. 
   Biff_Loman | Sep 08, 2008 05:16am | #11

   I hate plaster. I hate cutting holes in it for electrical work, I hate patching it, I hate trying to find studs behind it. I especially hate wood lath.

   If it were my house, I'd lose it in a heartbeat. But it's not really YOUR house, is it? If you're renting it, I'd punch a bunch of holes, blow cellulose, do at least a B+ patching job on all the little holes and be done with it.

6. 
   alwaysoverbudget | Sep 08, 2008 06:30am | #12

   this your first rental?tell me a little of what your thinking,how old is the house,what kind of neighborhood, what did you give for the house and what is the selling price for a nice house in the neighborhood. whats your piti and what do you ecpect to rent it for.

   i ask these not to be nosy but this is what i do,landloring,and unless there is some sort of circumstance involved  that makes this a exceptional deal,your wasting your time and money.but tell me more.larry 

   if a man speaks in the forest,and there's not a woman to hear him,is he still wrong?

7. 
   Jeff_Clarke | Sep 08, 2008 08:35am | #13

   I don't know what your level of commitment or ability is but you can carefully remove the baseboards on the exterior walls and hole-drill each bay (2 3/4") for blown-in fiberglas or cellulose from the inside - then put the baseboards back.   Sometimes the plaster isn't even present behind the baseboards.  You can probe up in each bay to see if there are fireblocks or nailers (usually are, even in balloon frame) - if so you'll need a 'high hole' as well as a low hole.  It is possible to go high enough to then come back and install 3" crown (rather than patch the holes if it suits the interior trim.

   Patching exposed holes ... you make up strips of 3/8" x 4" plywood that you can slip into the holes - (2) drywall screws and liquid nails to secure in place, expanded lath circles stapled to plwood.   Use patching plaster to near-flush then drywall compound.  Not for the faint of heart ... but then neither is a plaster tear-out.   Test it first for asbestos.

   Jeff

   
   

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   Edited 9/8/2008 1:50 am ET by Jeff_Clarke

1. 
   BryanSayer | Sep 08, 2008 05:00pm | #16

   If the exterior walls are studded and have lath then when you remove the baseboard you will find A LOT of the first coat of plaster piled up at the bottom of the stud bays, sometimes in huge chunks. It is from the drippings of the first coat.I find that I need to remove about the bottom two or three strips of lath to have enough room to remove all the drippings. I wonder if there is a name for them, like tailings or something?Of course if the exterior walls are solid masonry, non of these applies. But then the OP wouldn't be insulating either.BTW, I'm with the punch holes and blow in group. Even re-wiring is pretty easy. Removing all the plaster and lath will create a huge mess, and getting the trim back on nice and flush is a real pain.

2. 
   sisyphus | Sep 08, 2008 10:50pm | #21

   Thats a interesting point about asbestos. I was wondering whether lead paint could be an issue in the OP's jurisdiction. Otherwise tearing out plaster and lath is just monkey work.

8. 
   Clewless1 | Sep 08, 2008 04:10pm | #15

   Choices, choices. You could drill/blow from the inside ... or get lucky like one guy said (behind the baseboard). You could drill and blow the outside (pull siding or drill and patch (which I generally wouldn't recommend and it depends on the type of siding)). You can do as you mention (rigid on the inside) ... but there are issues that you need to think through well including: bumping out ALL electrical boxes on the ext wall, trimming all side/intersecting wall baseboards shorter, retrimming around all windows and doors (one of your biggest tasks), and replacing baseboard trim and attaching through the insulation. Where are you located? A MINIMUM of 2 inches polyiso would likely be your choice ... 3 inches in colder winter climates. You lose 2-3 inches of space ... maybe an issue, maybe not.

   Not trying to discourage you or influence you one way or the other. Rigid insulation inside is a simple concept (and the plus is you thermally break much of the framing), but the details can be a lot more work than many people realize ... you need to think about all the details. Done right it can work well.

   Not considering residing I take it? Option there ... rigid on the outside ... but again, some issues and details.

   Ripping out plaster ... a big job, but many people have done it (including myself).

   Drilling and filling includes both e.g. cellulose and maybe foaming (I know nothing about foaming a cavity like this).

   Existing construction ... hampers an otherwise easy task ... sort through your options ... do what is best under YOUR circumstances. Whatever you do ... do a good job.

9. 
   IdahoDon | Sep 08, 2008 08:15pm | #17

   If he wants to rip them out, you might want to let him.  After doing once a person has a much more realistic view of the process.

   Have him do one room at a time if possible so if he gets sick of it you will lose as little time as possible.

   You might find that something like r60 in the attic and a few inches of rigid foam under the floor will help a great deal with no wall work.

    

   Beer was created so carpenters wouldn't rule the world.

1. 
   rasher | Sep 08, 2008 09:11pm | #18

   Rental house? Don't insulate it at all!Blow some insulation in the attic.
   Install new storm windows, caulked well.
   Caulk any other remaining air infiltration.
   MAYBE consider insulating under the floor joists at the water table.Call it good.
   Tenants don't know anything about insulation, and won't place any value in an insulated house. If anything, install new high-efficiency HVAC and show your tenants that. They'll be pleased as punch...

1. 
   frammer52 | Sep 08, 2008 10:10pm | #19

   That is the approach to take if you are not paying for the heat, if you are, retro the cellulose. 

   Taking down lathe and plaster ranks as one of my least favorite activities, right along side of unplugging sewer lines>G<

10. 
    florida | Sep 08, 2008 11:46pm | #22

    If you're gong to rent the house you'd better figure out how much additional income insulation will bring you before you start work. Your payback could be eternal.