I think that one of the best things you can do is follow along AFTER your builder does his thing and look for gaps. I'd like to think that things have gotten better - but there's always room for improvement. Code is usually lowest common denominator.

Spray foam gaps and cracks yourself, stuff insulation into small openings that might get missed, etc. Buy insulated outlet cover plates, insulate the back of your attic pull down, or knee wall doors, and weather strip around them, etc.

At the time there's a blower door test (if you are doing that) it's already too late.

Be aware sealing a building and not providing an air exchange system will usually cause a 'Sick Building Syndrome' when stale air cannot be exchanged with fresh air. That should not be a problem with a new home, since building codes usually specify such a system.

Can be a huge problem with older homes, built before the SBS was recognized and planning was instituted.

here you go, the best air sealing info I've come across with simple diagrams

very comprehensive overview of standard air leakage sites.

http://www.southface.org/wp-content/uploads/2016/07/georgia-code-iecc-appendices-2009-1.pdf

the first page is a check list, the other 13 pages show you how

and were to seal.

if you have questions, post here & we can help you out

with material choices for air sealing.

if you know where to seal, and at what stages of construction

you'll benefit from this document. I send this link to all my

new construction clients. we verify air sealing with blower

door at time of client's choosing.

this link applies to both new & existing homes.

where are you located?

best of luck.

I'm in Manlius NY which is near Syracuse.

This will be my 4th new home and the second since I started taking an interest in insulation and air sealing. The last house was custom and I had a lot of day to day input into the details. This one is more of a tract home where I hear "this is the way we do it" a lot. Because of the budget we are using fiberglass batts in the 2x6 walls (R21) and loose blown in something in the ceiling (R49).

Code requires the house to beat a 7 ACH blower door test. I am hoping to beat that by a lot. Once the test is done and we have lived there for a little while I will evaluate whether we need an ERV - I had one in my very tight previous home.

I hope to bully my builder into having the sheet rock sub apply a continuous bead of glue to the top and bottom of each piece of sheet rock. I will also caulk the electrical box/SR intersection. I may also get into the attic before they insulate and see what needs to be caulked/foamed.

Thanks for all the replies.

'Air tight' light cans aren't really very tight. When I installed mine, I could see light through them. Also, the warm can can create enough heat to melt snow on the roof, leading to ice dams. I built boxes around mine and sealed them up. All of the electrical boxes in the ceiling leak air, as do all of the wiring penetrations.

If they're not using rigid foam over the sheathing, or some such thermal break, your R-21 walls are actually going to perform at least 25% lower than that. There's a lot of thermal transfer through the framing.

Our ICF house is the first fully insulated and sealed house I've lived in in my 60+ years. The comfort and energy savings is shocking, to put it mildly. I built the house myself, and spent a lot more time and trouble detailing it than a contractor would have. I don't know if I'll ever recoup my investment, but the comfort makes it worthwhile.

All good points Mushcreek

I got up on a ladder and examined my "air tight" cans and was actually impressed. Compared to the supposedly airtight cans we used in the last house 8 years ago these are much better. After closing I will explore boxing mine in. I will also take a shot at sealing the sheet rock to the perimeter of each of those penetrations. The idea of either of those things would blow my insulation subcontractor's mind.

The wiring penetrations shouldnt leak. They are all foamed and I checked each one.

Sadly, no rigid foam on the exterior. I tried. This is a tract home and the builder has never done it. I didnt wan to be the guinea pig.

Some day when I win the lottery I will build my own home and do things the way I want them done. That sounds ideal.

energy_rater_la - that PDF is awesome!

My house is not conventional construction - but that is wicked thorough - thank you!

Code requires the house to beat a 7 ACH blower door test.

That's a p*** poor limit, to put it mildly. Especially in your cold upstate climate. IRC 2015, effective in NYS as of April 2016, limits air changes to 3 per hour @ 50 PA as per IECC 2015, Table R405.5.2 (1). Wonder where that 7 ACH figure came from.

I find that once icat recessed lights are installed, that the air leakage

site becomes the cut in the sheetrock. I use mastic tape to seal

from the face of the sheetrock into the housing of the icat light.

then the trim kit covers the mastic tape.

glad you liked the link jannicone, when soutface inst. reworked

their website the name of the link changed. it took quite a few

email to find what they re-named it. but yeah...great info!

The 7 ach is from the previous code which was in effect when my building permit was issued.

Taping the face of the sheetrock to the bare metal of the can is a lot easier than getting in the attic and foaming that connection from the other side. thanks for the idea.

Spent the day caulking and foaming (after the builder already did both). One area I would like to address is on the exterior where the osb comes down over the sill plate and concrete foundation. I would like to seal the osb to the foundation from the exterior. I am thinking a caulk of some sort. Any suggestions? Keep in mind it's in the 30s here in central NY. Thanks

Thanks Dave and others looking to build better homes through air-sealing. Current blower door test minimums, used to measure airtightness, are very weak compared to higher performance projects and certifications. Most of those building homes seem to be getting away with skipping this basic building code. It's similar to a time before insulation requirements.

Address air-sealing in the planning stage. Most of the lowest fruit exists in design and specifications but it's best to involve an informed builder as much as possible.

Wall area is one of the easiest locations to air-seal, but some OSB can leak right through the surface. Assuming your builder or designer chose OSB that's airtight (or even if not), it's best to tape all panel seams. I would tape OSB to concrete as it's unlikely your builder achieved airtightness at the sill. Framing to masonry is one of the leakiest transitions in a home and one of the most important to seal.

You will probably have to use primer and a vapor permeable tape would be preferred. If that's too much, caulk is a minimum and should be the highest quality urethane available.

If it's not too late to specify spray foam or dense pack for your cavities, strongly consider it instead of any batts which are usually poorly installed. Better air-sealing within the cavities (or applying caulk to framing from interior) can be helpful, but the best results seem to be achieved at the sheathing or drywall layers. I'm a fan of skipping the airtight drywall approach and concentrating on the exterior sheathing whether it be with a fluid applied housewrap or taped foam and structural panels.

Windows offer a lot of opportunity. Avoid sliders and double hungs for swinging doors and casements. Use a belt and suspenders approach to sealing the rough opening, between framing and window unit. I think interior tape, backer rod and caulk are much better than canned spray foam. Don't waste money on cheap canned foam, I've seen it turn to dust in a matter of weeks.

Penetrations need to be scrutinized, especially exhaust vents. Dryer vents and bath exhaust vents need quality inline dampers or wall caps to contribute to airtightness. Pipes, ducts and wires need caulk around their entire perimeter but quality, well installed tapes are a best practice here as well.

Thanks Spring time. Some day I will build a truly custom home and get to do all the things you mentioned and more. Unfortunately, this isnt that build. This is a tract home where I hear "we don't do it that way" a lot. I've had to pick my fights. Even when I have wanted to pay for something to be done a certain way I haven't always been able to get it.

We are at the sheet rock stage so I think most of my air sealing and insulating opportunities have passed. What's been done so far:

- Walls are R21 fiberglass batts. I would rate the insulation job as just about a level 1 job. Ceiling will be R49 blown in.

- wire chases, electrical boxes, ceiling fixture boxes have been foamed.

- Seams in the 2x6 framing have been caulked.

- Horizontal seams in the OSB has been either caulked or foamed.

- Corners have been foamed.

- Windows foamed

- Attic baffles foamed. This was to get some extra R value in the shallow space between the top plate and the attic baffles. The installer may not have known what the purpose was because he seems to have gotten foam everywhere with just a little in the spots where I wanted it.

- Some of the cavities were foamed at the junction between the OSB and the 2x6s. The batts were installed before I was able to do them all.

- Basement rim joist foamed

- Concrete block walls in finished section of basement has R10 2" foam sheathing and will get FG between the studs.

Things that I will try to do going forward:

- Seal the OSB to the concrete block at the exterior. Springtime - can you recommend a primer and tape for this purpose?

- Seal the perimeter of outlets and recessed lights where they intersect with sheet rock.

- Seal the sheetrock to the floor.

-If I can, get into the attic before insulation is blown in and seal the sheetrock/framing lumber seams.

- Once the house is completed, permanently seal the attic access hatch.

Much of this I have/will do my self on nights and weekends without the builders explicit approval. I assume the manager knows because much of it is obvious.

We do not currently have an HRV planned. I am going to wait and see what the blower door test reveals and if I need one, I will install one.

permanently seal the attic access hatch.

And when you need to check the attic?

I glue layers of XPS to the hatch and pull it tight against a gasket with hooks and eyes.

Springtime Builders

cheap canned foam, I've seen...turn to dust in a matter of weeks.

Years later I've seen windows I've had foamed with handhelds removed and the foam had to be Sawzall'ed out.

By permanently seal I mean caulk and or foam the gap in the sheet rock. i am also thinking that i will move the attic access to the garage rather than the master closet. This is a ranch. i like your strategy though.

Springtime - thanks for the links on the window install. Even though we're not using conventional framing - some interesting ideas in there - especially the backer rod and caulk (of which we are familiar since we're using the concrete sandwich panels for the overall shell construction.)