Basement reno - How do I effectively insulate my basement?

We often get asked 'whats the best way to insulate a basement' particularly when people are doingbasement renovationsandenergy efficient upgrades. The honest question, is there simply is no single 'best way' to do it, so if someone tells you that, they're wrong. It depends on yourclimate zone, thewater table on your property, and your own personal preferences for material selection, and the list goes on...

So the best advice we can give you is to learn what NOT to do in a basement, then when a general contractor suggests doing it the way 'they've always done it', you can you can tell them no thanks, if I want mushrooms I'll go get them at the grocery store, I don't want to grow them in my walls. So start here with the building science basics, we've made it simple (and even fun we think) to learn -

How to prevent mold when you insulate your basement

That's the science 'for dummies' behind it, and more directed for renovations. there is a page for building basements properly in new homes -

Best practices for building basements in new homes

Now that we got that stuff out of the way.... here are some more direct answers to your questions. There are a lot of questions in there so I've copied them here below so neither of us get lost :

Question:

Concrete Foundation: Durofoam EPS (1.5" or 2"?) +wood stud with Rockwool R14 +Drywall +moisture/vapour barrier latex paint. Which EPS thickness should I go with?

Answer:

You’d be better with the 2” EPS on the walls if you can spare the space. That would give you a bit more thermal protection, and at 2 inches EPS is about 1 US perm, which is the permeability rate at which a material is classified as a suitable vapour barrier for residential construction. That would better prevent moisture from the ground and concrete walls from migrating inwards.

Question:

Concrete Slab: DMX aiflow dimple mats +(3/4" EPS, needed?) +OSB +flooring of choice

Answer:

First on the floor EPS – yes it is a very good idea to insulate the floor, if it was built in 1983 it is unlikely there is currently any insulation under the floor. But ¾” is only R3, so how much head room do you have and how much can you spare? If you have the space I’d add more than that myself, partly for energy efficiency, but also for comfort as you seem to be planning this as finished living space. R3 would leave your feet pretty cold.

And from a construction point of view, you might find that the floor is a little spongy if it rests on foam only. Alternatively, I would suggest maybe you lay down some sleepers (2x4 or2x3) and insulate between them. This would allow for thicker insulation and give you a solid nailing surface for your subfloor and final flooring.

至于酒窝matt，这是一个好主意，但要记住，它能承受的水量是有限的。这里以前有过洪水吗?或者水位很高吗?你会放一个水泵进去吗?That’ always a really good idea and a wise investment for avoiding future damage and expensive repairs.

Question:

头球/篮筐托架:不确定…既然这是高于等级的，但在地下室，我如何分层，并把它与上述墙壁保温方法绑在一起?我是在边缘搁栅和槛板的缝隙周围添加声学密封胶还是膨胀泡沫?下一步，我要填充边缘托梁腔岩棉，然后EPS +石膏板?或只是夹层+密封EPS板，以建立它的基础墙保温。

Answer:

This is one of those places where spray foam really shines, and I don’t mean the stuff you get in a can at a box store but the kind that is installed for you. It fills all the holes, it is an air and vapour barrier and has a high per-inch R value. Besides spray foam, yes, you could put Rockwool in each cavity, then EPS in that same cavity (sealed to the wood at the sides) and install drywall over it.
Accoustic sealant does a great job, but it is a nightmare to clean up, so keep that in mind.

Other questions:
How do I adequately insulate around water meters, electrical panel or rough-in pipes that are very close/adjacent to the exterior foundation walls?

Answer:
Spray foam and tape. Which works best would probably change on a case by case basis.

Question:

Will there be an issue with thermal bridging or vapour with having one insulation system (old) adjacent to another (new) and only separated by wood stud?

Answer:

我不完全理解这个问题。我需要知道你指的是哪一部分，是什么类型的材料。因为这是一个问题本身，也许可以在一个单独的问题线程上开始它，包括关于你计划保持的当前程序集的细节和关于你计划添加的程序集的细节，我们可以看看它是否有意义。

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