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What to do after you've spent a year and a half building a super insulated building, so air tight it's poured in concrete?

Drill big fat holes in it of course!

We've entered my most dreaded phase of building.  

It's utility time.

I despise this stage because there is so much work, so much money invested ... but you can't see it.  In other words, you aren't getting a finished project.  You are getting what looks like a freeway interchange of pipes to be hidden inside your walls.  It's going to be a long few weeks of drilling holes in the interior walls of the Momplex and pushing pipes and vents through, and later pulling wires though.

Where to start?  These are the systems we will have in the Momplex:

  • HRV (heat recovery ventilation)
  • Plumbing Water Supply (hot and cold)
  • Plumbing Drainage
  • Phone/Telecommunication/Internet/Stereo/Cable or Satellite TV/Etc
  • Electrical
  • Central Vacuum (have you seen the automatic dustpans?)
  • Heat System and Thermostats
  • Dryer Vents

I know, these new houses are really getting complicated! But a little work now will sure be nice for Mom later on!  

So where to start?

Because everything has to run in the walls or floor joists, sharing the same space, starting with the biggest pipes makes the most sense.  

And the HRV system has the biggest pipes at 6" in diameter.  

An HRV system basically pulls stale or moist air out of the home, and as it goes out, it exchanges with the new air coming in, warming that new air up.  So it's more controlled and efficient than cracking a window.

To make sure we had a balanced HRV system, that works optimally and keeps the air fresh, dry and warm, we worked with a local ventilation company that engineers the design and supplies the parts and oversees you DIYing the installation.  By going the DIY route, we are getting the best possible system, but saving over $3000.  

Are you wondering how we run a 6" pipe through a 2x4 wall?

Well, you squish the pipe of course!

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Step 1 Diagram: 
Step 1: 
A flat pipe is twice the work to drill holes for though.
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Step 2 Instructions: 
Normally you'd just drill one hole. <p><br /></p><p><img src="" style="width: 470px;" alt="" /><br /></p> But we will need to do double duty to squish the pipe to fit inside the 2x4 walls. With all the holes we are drilling, we invested in a good hole saw kit. Yep, no more smoking (yes, smoking as in burning smoking) wood as you try to drill a 4" hole.
Step 3 Diagram: 
Step 3 Instructions: 
This hole saws actually work like a saw blade, running in a circle, instead of teeth rotating in a circle, so the sawdust is spit out as it bores a hole in no time flat.
Step 4 Diagram: 
Step 4 Instructions: 
When you've got twice as many holes to drill, speed and efficiency are very important.
Step 5 Diagram: 
Step 5 Instructions: 
Then it's just connect the dots with a saws-all.
Step 6 Diagram: 
Step 6 Instructions: 
One down ...
Step 7 Diagram: 
Step 7 Instructions: 
to early to count how many to go. Just keep repeating to yourself ... we are saving $3000 to DIY the installation ourselves.
Step 8 Diagram: 
Step 8 Instructions: 
Throughout the Momplex, inlets and outlets are hung according to the engineered plans where air will be pulled out of the Momplex, and then new air replaced inside the Momplex. The air is pulled from rooms including kitchens and bath, where moisture is created. New fresh air is then pushed into bedrooms and other rooms. This keeps the air circulating throughout the home.
Step 9 Diagram: 
Step 9 Instructions: 
From the inlet our outlet, we run the flat pipe.
Step 10 Diagram: 
Step 10 Instructions: 
And that goes down through the wall and through the holes drilled in the floor.
Step 11 Diagram: 
Step 11: 
Man that guy is good!
Step 12 Diagram: 
Step 12: 
Underneath, the flat pipe is converted to a round pipe with a special corner fitting.<p></p><p><img src="" style="width: 470px;" alt="" /></p><p></p><p></p><p></p><p>Here's a close up for you. &nbsp;</p><p></p><p></p>
Step 13 Diagram: 
Step 13: 
The round pipe just needs a circular hole drilled.
Step 14 Diagram: 
Step 14: 
It's much easier to drill these with the hole saw kit because it's just mark the center and drill away. Half the work, half the time! We are very grateful for our friends Bob and Martha for loaning us this right angle drill. It is a lifesaver!
Step 15 Diagram: 
Step 15: 
Pretty quickly, a row of holes can be drilled through the joists. <p><br /></p><p><img src="" style="width: 470px;" alt="" /><br /></p><p><br /></p><p>And then it's just take your pipe</p><p><br /></p><p><img src="" style="width: 470px;" alt="" /><br /></p><p><br /></p><p>And cut it to length.</p><p><br /></p><p><img src="" style="width: 470px;" alt="" /><br /></p><p><br /></p><p>And snap the pipe together. &nbsp;Of course every seam or joint of ever pipe gets taped to prevent air escaping and creating an inefficient system .. but that's another story ... and another day .. er few days.</p><p><br /></p><p><img src="" style="width: 470px;" alt="" /><br /></p><p><br /></p><p>Then the pipe gets put in between the joists.</p><p><br /></p><p><img src="" style="height: 360px;" alt="" /><br /></p><p><br /></p><p>Where the pipe runs between joists, parallel, blocking is placed in the joists to support the pipe.</p><p><br /></p><p><img src="" style="width: 470px;" alt="" /><br /></p><p><br /></p><p>There is pipe everywhere in the basement ceiling.</p><p><br /></p><p><img src="" style="width: 470px;" alt="" /><br /></p><p><br /></p><p>Grandpa Tim helped out, and although it seems like a ton of work, the HRV system was done in 3 days. &nbsp;Not bad for a $3000 savings!</p><p><br /></p><p><img src="" style="width: 470px;" alt="" /><br /></p><p><br /></p><p>I think we need to take Grandpa Tim on vacation!</p><p><img src="" alt="" /><br /></p><p><br /></p><p>And if I say so myself, even though I dread this stage and gripe that nothing gets "done", those are some pretty pipes!</p><p><br /></p><p><img src="" alt="" /><br /></p><p><br /></p><p>We still have to hook the HRV system up to the piping. &nbsp;Can you see the green box? That's the boost button, guaranteed to suck moist air right out of bathrooms and prevent windows from icing up and mold developing. &nbsp;</p><p><br /></p><p>It will be interesting to see how the system performs!</p><p><br /></p><p>So what do you do in your area for ventilation? &nbsp;Do you just open windows? Or do you have an HRV system? &nbsp;Do you like it? &nbsp;Or never use it? &nbsp;It's interesting to see how other homes keep air fresh and dry without throwing good heat out the window!</p><p><br /></p><p><br /></p>


This is the first time I've ever heard of HRV systems. Where we are, the humidity is so high, I doubt opening a window would help at all. I think we just deal with the mold/mildew.

Hi Patrick, the HRVs are relatively new and most often used in cooler climates, as it's just a ventilation system but has heat recovery added to it. The theory is as the warm air is drawn out, it warms the cold air coming in. Any heat recovered when you are going from +68 to -60 ..... well it's something.

It's actually really dry where we are in Alaska, but what happens is when you shower or use dishwasher or boil water, the moisture gets in the air. It has nowhere to go, so it starts freezing up on windows sills, hence the charming frost covered window sills. But the reality is the frost then destroys your windows sills and starts molding your drywall.

Moisture can also build where the vapor barrier has been compromised, as the warm moist air is leaking out and freezing instantly. You'll know in the spring when gallons of water start dripping out of your ceiling.

It's interesting to see how different climates require different systems.

I'll have to look into it. We tend to keep windows/doors open late autumn - early spring, but any other time it's just too hot!However, we just love to have fresh air! (or as fresh as it can be in an overpopulated valley that keeps the smog stagnant)...Thanks for introducing this to us!

I can see how that's dreaded... Glad you guys pushed through and got 'er done!

HI Gina, you are so lucky! We can open our windows for about 2-3 months and that's it. It's so nice to have fresh air, so hopefully this HRV does the trick! Here's to the next five or six utility systems going fast and easy!

I am so glad to see more of your momplex posts, I check almost everyday to see the progress. I have also never heard of an HRV system, it actually seems like a great idea. We have bathroom fans that "pump" the moisture laden air outside, but they're very inefficient and the walls are almost always damp. Also, I love my mother-in-law's central vacuum. It is so much easier to clean up the kitchen floor when I can just sweep it up to the vacuum right on the island.

Hi Melissa, thank you! It's been tough to carve out the time with the book releasing and then just being burnt out from a busy year, but we are super excited to get her done!

We have the bath fans in our house too and it's not enough for us either. I'm glad you like central vac - I've heard mixed reviews but I love those power dustpans!!! I think I'd sweep my floor every hour with one of those in my house!

Yes, we use an HRV system, just like yours. All our ducting is done, we just need to connect it in the utility room. But even without it, this new house we are building is already less humid then our 10 year old house we currently live in. I look forward to seeing the difference when the system is actually turned on! And the least favorite part for me with all the ducting was trying to figure out the best route for it to take with the least amount of bulkheads. Then how to make those bulkheads look intentional and decorative instead of merely functional. I did not enjoy that stage of the process.

Oh Chantelle, I hear you! We had to redo the kitchen plans to make things work! But the Ram assures me fresh clean air is worth the vents. We'll see - can't wait to fire the system up and let you know if it does what it says it should!

This may be exactly what you implied by including "internet" in your list but if not I would look into wiring the house with quality network cables/jacks. Wireless networks are great, but good signal is pretty difficult in many cases.

Having Cat-5/Cat-6 cable running to a central patch panel would let you work with standard home electronics (easily upgrade-able standard router and cable/dsl modem) and provide vastly superior performance everywhere in the house. And, since wireless is convenient, you could always hook a wireless router into any of the network jacks and have a wireless network from that point.

If internet use is a consideration (and most every device one buys today has the capability) having a reasonable infrastructure in place could make life a lot easier.

Just a thought,

In theory, theory and practice are the same. In practice, they are not.

David's right. We've had many home networks in as many homes (on our ninth right now), and those that we've been able to have over wire are hands-down better than wifi. Aside from the health concerns that adding any kind of radiation to your home brings, wired LAN's (Local Area Network) are WAY faster than wifi. Much better, overall.

So, run some CAT cable in your walls, and wire up a jack in each room. That allows you to have more localized wifi (if you choose to use it at all), instead of bathing the entire building in the signal. I've been stuck with wifi for six months now, and I miss the wire.

It is not necessary to change. Survival is not mandatory. -- W. Edwards Deming

Hi David thank you for the tips on the internet! I keep telling the Ram that wireless is the future, and he keeps saying he's still wiring in cat-5 as you recommend as well. I have to agree, we certainly won't regret putting it in will we?

Grandma's kinda hip (she likes to facetime grandkids and skype) so we might have to put some iphone accessories and such in too ....

My mom has a central vac and has two automatic dustpans in her kitchen. Coolest thing ever. With the central vac, I could take it or leave it. I view it as I am either lugging around a vacuum or a bulky hose, but the one reason I would choose central vac or over a nice vacuum is the automatic dustpans. Best thing ever! No more bending over. No more dust pans. I hope your Moms each get one in their kitchen.

Hi Nicole, I went to a friends house the other day and she showed me her automatic dustpan and I seriously started brainstorming how we could just do away with baseboard trim and replace it with a power dustpan. Then I could just turn it on and the house would be swept!!! Oh I would so abuse that! I'm with you on the hose being inconvenient, but since we will mostly go with hard surface floors, it's the dustpan that will get used the most. And also we are considering carpeted stairs (ugh, I know!) but with Mom going to live past 100 in there, carpet seems to be the safest for her to use the stairs the longest.

Is this an in the earth heat exchanger? I don't remember you posting about putting one in while you were still working on the outside. The idea of an HRV makes perfect sense. Like Melissa my home only has a bathroom fan which does not work well at all. I assume an air filter could be attached to the system as well? Keep up the great work. I love reading the posts.

Hi Christopher man I wish we could do the geothermal heat, but from everything I read (and no success yet that I know of) we just don't have the thermal heat to make it work up here in Alaska. Well, I should rephrase - the cost to install a system that could keep up in Alaska with our lower ground temperatures would no be sensible for us :( here's hoping someday!

Our bathroom fans suck! Or should I say they don't suck! Excuse my language, but it's frustrating. Hoping the HRV system does the trick. Yes, you can add an air filter, so even in a warmer climate, there's still benefits.

Thank you for reading and keeping us inspired!!

Hi Klynel, Great observation and question! Drilling holes in joists does weaken joists, but the joists are engineered and sized for spans to allow for it. The joists we have actually have predrilled holes that you can knock out to make running wire and plumbing through. But nothing for the HRV holes, so we had to drill them.

I would love to have a heat recovery system. Or properly ducted bathroom fans. Or a kitchen exhaust fan. :P I'm guessing retrofitting with an HRV is even less fun!We aren't quite in Alaska (although there is a sign that says it's the scenic route to Alaska near us) but we can get to -30 C at night (-22 F) and anytime we get close to that we get ice on the windows on the second floor at night, even the newer ones and it's pretty dry here. Lots of breathing with 6 people I guess!

Hi Kim, our house is like that too without an HRV - the bath fans don't vent that well and when they do, it just sucks nice warm air right out of the bathroom! We thankfully have great windows on our front that do not ever build ice! But our bedroom windows were low budget (we were kids with a baby building paycheck to paycheck) and we pay for it by having to cover the windows with plastic window seal every winter. We are considering retrofitting our own home - will see how the HRV performs for Mom first!

And yes, it's crazy what having people over for us (there's just three of us) can do for our moisture inside!

Another vote for wired ethernet, or if it's not in your budget and your not going to use satilite TV, look at MoCA. it's about 70 for each connector box, but 2 added advantages, first is the cost VS connections, everyone adds coax to bedrooms, living rooms and offices, some to the kitchen. so your already saving on cable, connectors and faceplates,ETC.
Second it's rated for faster than 100mb ethernet.

Verizon uses it for their FIOS service, so those of us that have that need one less box. because you can use a switch with them, you usually can get by with just 1 in each room you need wired, amazon has Actiontec 2 packs for about $120 and the singles are $70. could save a ton VS wiring a whole house. The cost of cable alone can justify it, let alone tools and connectors, patch panels and the like. If your a satilite user, MoCA isn't compatable, their is overlay in the frequencies.

so a quick suggestion on thise "squished" pipes - we have those running to the second floor for our central AC, and because I had no idea where they were - I accidentally screwed right into one of them installing closet shelves one day :( Might be worth it to draw yourselves a little map where all the pipes and wires are running in the walls now to avoid costly repairs later down the road.

We live in the Pacific NW - all the humidity, but none of the bitter cold! We just have fairly powerful fans in the bathrooms and kitchen. "Cold" for the folks here is anything near or below freezing. I think if they ever saw a minus sign in front of a number, they'd drop dead from shock!

But I hear you on the light - my husband pretty much only sees the sun when eating lunch. It's dark when he leaves for work, and dark when he gets home, and he works in a lab with no windows for most of the day. We're used to it, as we lived in Minnesota at nearly the same latitude for several years, but there are some California transplants who really struggle with the day length!

We ran a small hotel in Scotland (damp damp damp) and used to battle with mould and mildew. When we upgraded 3 rooms we installed a HRV system. After a full year's use, those hotel rooms and bathrooms are pristine, with not a speck of mould.

If I ever buy a house, I'll be getting on installed PDQ

I'm catching up on all your Momplex posts and loving all your progress!

Just to chime in on a few comment topics - I love the convenience of wireless, and the chances that your two elderly mothers will need the super fast speeds of wired seems pretty slim. BUT wired is often essential for even decent wireless. Especially in a well sealed home. I don't know how sealed your interior walls will be, but my wireless signal has trouble making it through my walls. And with those concrete exterior walls, the second mom steps onto the patio, her laptop will lose any signal. Wired allows you to put wireless boosters all over the property, and extends your wireless signal where you need it. Plus, it gives you a better shot a "future-proofing" the home, which is what you are after.

As for the stairs - how about a stair runner? Still allows for the traction to hep aging moms, but more attractive and easier to replace and clean (no trying to vacuum the carpet around the stair spindles).

Building a house is not an easy task but if you put some effort you can do a nice work.I've recently finished my house construction and I've already decorated it.I just have to contact an AC Repair Tucson Company in order to fix the cooling system and after that I will move there.It wasn't easy to build my own house but I enjoyed to do it.