Insulation (sales, house, buy)

[NoviceDude]

Am getting my house built in regency park plano by grand homes,
question on insulation. these are what comes standard please let me know if this insualtion is good enough or do i need to add more insualtion.
1. R-13 wall insualtion
2. R-19 batted insualtion on sloped ceilings
3. R-30 batt insualtion on floor joist over garage
4. R-30 blown insulation on flat ceilings
5. Poly-sealed foam base plates
6. Poly-sealed foam wiring and plumbing holes from attic

Thanks.

[bricor]

I thought I heard the standard now for ceilings is R-38 instead of R-30.

[SouthernBelleInUtah]

R-38 is what is rec'd for ceilings and has been for some time. Sloped ceilings are still ceilings - should be the same. I added extra blown insulation to my attic a few years ago and noticed an immediate difference. You can always get an insulation contractor to blow more in flat attic but the sloped ceiling has to be done at construciton. Insist on it!

[loves2read]

those are what the city has set as minimum for code--
you need to have radiant barrier decking used for your roof--that should be part of every city's construction code--it is not that expensive and I don't know why they keep dragging their heels to make it mandatory--
If you could get them to actually use a vapor barrier that has a reflective nature THAT would be effective heat shield for the exterior walls and help with cooling costs significantly--
YOU can add insulation to attic spaces that are reachable but not to the sloped ceiling--or to the walls--so get those beefed up NOW during construction because they can't be done afterwards...

PLEASE tell us you have a realtor helping you buy this house--not just the sales person at the office...

this is a tip--make sure YOU are there when they are going to blow the insulation--check the # of bales that they are using NOT the depth of the insulation after it has been blown in to the attic spaces---the bales should say what area each is supposed to cover for the R-factor--or find out on some building web site
(suggest gardenweb.com--building a home forum)...to find out how many bales are necessary to give you the R factor for your attic space--
get the dimensions from your plans or ask the builder...

just measureing the height of insulation after it is blown in (which is what they will probably show you to prove the accuracy) can be very deceiving since using extra air fluffs the insulation more than necessary (like using extra water to dilute coffee grounds or thin pancakes)..

the insulation is expanded but the air leaves and when insulation compresses there is LESS than you are supposed to have to ensure the level of R factor--
it is all about the DENSITY of the insulation--no the inches...if you understand the difference
an inch of steel is significantly MORE dense than an inch of water---you want dense insulation because that means HIGHER R-factor...

[CarolAnn64]

I know very little about any of this but as I type this, I am sitting in my home in FM as they spray on the radiant barrier. We'll see how it works.

As for the insulation, I too have been told R-38 for ceilings. Our home is older and insulation not adequate so this weekend, DH and I are blowing in more ourselves.

[Lakewooder]

Originally Posted by loves2read

those are what the city has set as minimum for code--
you need to have radiant barrier decking used for your roof--that should be part of every city's construction code--it is not that expensive and I don't know why they keep dragging their heels to make it mandatory--
If you could get them to actually use a vapor barrier that has a reflective nature THAT would be effective heat shield for the exterior walls and help with cooling costs significantly--
YOU can add insulation to attic spaces that are reachable but not to the sloped ceiling--or to the walls--so get those beefed up NOW during construction because they can't be done afterwards...

PLEASE tell us you have a realtor helping you buy this house--not just the sales person at the office...

this is a tip--make sure YOU are there when they are going to blow the insulation--check the # of bales that they are using NOT the depth of the insulation after it has been blown in to the attic spaces---the bales should say what area each is supposed to cover for the R-factor--or find out on some building web site
(suggest gardenweb.com--building a home forum)...to find out how many bales are necessary to give you the R factor for your attic space--
get the dimensions from your plans or ask the builder...

just measureing the height of insulation after it is blown in (which is what they will probably show you to prove the accuracy) can be very deceiving since using extra air fluffs the insulation more than necessary (like using extra water to dilute coffee grounds or thin pancakes)..

the insulation is expanded but the air leaves and when insulation compresses there is LESS than you are supposed to have to ensure the level of R factor--
it is all about the DENSITY of the insulation--no the inches...if you understand the difference
an inch of steel is significantly MORE dense than an inch of water---you want dense insulation because that means HIGHER R-factor...

Thanks, those are good suggestions. I have been looking into this. If you have the name of a good company, let me know.

[lh_newbie]

There's a big difference between what's generally done and what is actually recommended. Here's a link to the Department of Energy web site:

Energy Savers: Insulation and Air Sealing

Lots of info there, but more specifically, here's a link with specific recommendations based on your zip code:

ZIP - Insulation Program

The recommendations now are :

- R-15 in the walls (R-13 is a medium density fiberglass insulation, there is R-15 available).
- R-38 in cathedral ceilings (I'd actually argue this, you want the same as their recommended flat ceiling insulation levels).
- R-49 for flat ceilings

In that first link, please make note that there is more than just insulation that is important. Infiltration is also very important. Make sure they use a house wrap and the recommended insulation levels I put above.

Then look at the windows. If they're putting in aluminum windows, you probably want to ask about vinyl windows instead. The frames for vinyl are a little wider, but they insulate quite a bit better (generally speaking, you need to look at U-Factor and SHGC ratings to compare windows). SHGC is the % of sun heat allowed through, represented as a decimal value. 0.60 = allows 60% of suns heat to enter the home. On east, west and south facing windows, you want 0.40 or lower (0.35 is a pretty darned good number). U-factor is the inverse of R-Value. An R-value of 2 is the same as a u-factor of 0.50 (i.e. 1/2). U-factors of 0.40 or lower are also desirable. Getting both values at or below 0.40 is easily obtainable in vinyl windows and won't cost any more than aluminum windows - people like aluminum windows because the frames are a little more narrow. IMO, it's not that big of a deal, and the better insulation/heat reflection pays you dividends.

If you can get both of these recommendations - then you should be in pretty good shape. I'd guess your summer cooling bills would be 20-30% lower than your neighbors that didn't increase insulation values.

While you're at it - look at the HVAC efficiency, rated in SEER. Higher is better. 13-SEER is the federal mandated minimum. If you can upgrade to 15-16 - and preferable get a dual-speed or variable speed compressor AND indoor fan unit - then you'll really be ahead of the game. Upgrading to 16-SEER, dual speed unit should only cost $1500-2000 more - which will pay for itself in the first 5 years in energy savings. Since the units last 10+ years - IMO - it's well worth it. Dual or variable speed is nice, because the unit runs in "low" mode (which is more efficient than "high" mode) for a longer period of time and removes more humidity from the air.

Get yourself R-49 in the ceilings, R-15 in the walls, home wrap, windows with u-factor and SHGC of 0.40 and 16-SEER dual speed HVAC... you're neighbors will be incredibly jealous when your bills are 30-40% lower than theirs.

Keep in mind that people generally don't replace windows for 20-30 years and you can basically NEVER upgrade your wall insulation or add a house wrap. Since you'd have both of these up front, you'd reap the benefit of them. Save your energy bills and your proof of energy efficiency can increase your resale value. We're slowly retrofitting out 1976 home. So far, we've upgrade the attic insulation to R-49 and have replaced some of the single pane, aluminum windows with dual-pane vinyl windows (u-factor = 0.34; shgc=0.36) and have a 16-SEER dual speed HVAC system. Unfortunately, we cannot upgrade the R-11 insulation in the walls and cannot add a house wrap. Even without these two items - and with 70% old windows, our bills are literally half our neighbors (the huge difference is because they have about around R-18 in the ceilings and 10SEER HVAC system).

Brian

(PS: it's 90 degrees today, but not sunny, so our air conditioner has ONLY been running in "low" mode today)

[nsumner]

Grand Homes doesn't put radiant barrier in their homes in Regency Park. It is considered an upgrade. They charge about $1500.

You would think that when paying 400K for a home this would be a standard.

Naima

[cherokeerose1809]

For those with a radiant barrier, do you think it really made a difference before and after? I need to cool down my attic and looking for what would be best. Right now, only have some passive roof vents.

[Pete53FR]

I put in a power ventilator and it really helped.