Your site by the retaining wall and among the groundcover sounds pretty ideal for daffodils and arum. Daffodils like full sun while they are above ground (your tree will be bare of leaves then). They don't mind the shade during the summer, because they are dormant under the ground. You need to know that Arum Italicum Pictum is grown primarily for its beautiful, white veined foliage in the winter. The flowers are brief and not especially showy. It goes dormant, completely disappearing, shortly after blooming in the spring. A seed stalk appears in late summer to early fall that has bright red berries, followed by the big leaves that last all winter. I love it. I am NOT certain it would be winter hardy for you. I'm also not certain the leaves would be tall enough to show through your ground cover. The bulbs are not cheap, so be sure you know before you order them. You will have no problem finding white and orange daffodils. I cannot recommend varieties for you since you are so much farther north than I am, but this information shouldn't be hard to find. A free source would be your local Cooperative Extension Agent, or the website of an agriculture university in your state. When you choose the right kinds of daffodils, they will "naturalize", which means not only do they return faithfully year after year, but they multiply, so you have more and more of them with each passing year. You can let them clump up, or, you can dig them up every so often, break the bulbs apart and replant them. When you are just starting out, try to plant at least fifty. More is better. Don't plant them in straight rows, and don't spread them out too far. Plant them in groups of at least 5 to 7 bulbs, about six inches apart. After they bloom, LEAVE THE FOLIAGE ALONE. It needs to grow for a couple more months or three, so that the leaves can feed the bulbs underground and form the baby blooms for the next year. This is why the groundcover idea is so good. The dying foliage will be much less noticeable. There are many reputable bulb dealers. I use Brent and Beckys alot, plus McClure and Zimmerman. Old House Gardens has varieties that can be extremely difficult to find. They are also extremely expensive. Always see if you can find what they have somewhere else before you ante up. (You can find at least some of what they carry other places. And for MUCH less $.) You can also buy bulbs very inexpensively at Wal-Mart and their kin in the fall. As long as you know what varieties are good in your area, there's no reason not to. You will save a good bit of money, although mail order bulbs are usually larger. REad up on when your best planting time is, and buy your bulbs as close to that time as possible. Early is always better than late. Your bulbs will be fresher. Watch this forum come fall. There is always alot of activity as people swap information and advice on good varieties and good companies. I expect that people in your zone start planting bulbs in September or October.

The Aqua-Tough board is a tile-on board that supposedly has a waterproof facing. So the board face itself will be your water barrier. I'm not terribly familiar as I've never used it. With the AquaTough being your membrane, the poly behind the board being in lousy shape actually works to your favor, as you only want one barrier in the wall system. You'll probably need to detail/seal the panel seams and screw heads. You could build the niche, detail the seams, then use a topical membrane like RedGard or Hydroban to waterproof the seams. Covering the AquaTough with Kerdi would be a waste. It's a membrane over a membrane. Same with completely covering the AquaTough with a trowel-on membrane like RedGard or Hydroban. You could use RedGard of Hydroban to spot treat the AquaTough; at the screwheads, the panel seams, the niche seams. But again, I'll defer to whatever the Aquatough installation literature says in terms of how the seams need to be treated. RedGard is the least expensive of the three that you listed, and it's made by Custom. Home Depot carries Custom, so if they don't stock it they should be able to order it for you, or you could maybe order it online for an in-store pickup. I'm not sure how Home Depot works in that regard. If I confused more than clarified, my apologies.

I'm surprised no one answered your question. There are two issues here. One, insulating living space,or future living space. Two, addressing proper roof function. Soffit and ridge venting deal with the second but are complicated by the first. If the rafter bay is to be insulated, asphalt & some other roof materials require temperature control beneath them. The typical strategy is the use of "chutes" below the sheathing in consort with soffit/ridge. "Or should we have no venting and just spray everything with closed cell foam (or other foam spray)?" No venting, with any insulation sounds like trouble as regards issue number two. The advantage of the spray ins is inherent vapor barrier. Look into a new roof on sleepers with that plan. That would enable full depth insulation AND roof venting.

Odors are just one component of cooking ventilation. Heat, Odors, Grease, Steam, and Smoke are all what is removed by good ventilation. Those “indoor smog” pollutants affect your indoor air quality negatively. Having them stay in your home affects your health. Multiple studies show that ventilation of cooking products improves that indoor air quality and keeps you healthier. While a retrofit situation may not be able to strive for the ideal, in 85% of my designed from scratch kitchens, the hood will always be specified to be larger than the cooking zone. It is ALWAYS discussed as the ideal, with any client being fully informed and signing off on the consequences of any other choice. When there is is no other choice but to have the same size, planning for it to be as deep as possible is the best solution to limiting the width. In all cases, it is the cooking appliance below and cooking style that determines the CFM needed for ventilation. You will have a low number and a high number based off of that cooking appliance. A high BTU cooking appliance will always have a much higher low number than a consumer grade appliance. Cooking style will increase that base number of the acceptable CFM span. It will never decrease that number. A Wolf range in a kitchen with someone who uses it as an ornament will still need a 600 CFMhood above, merely based on it’s potential. If that potential is lived up to by it’s cook, then that top CFM number will increase. It is the choice of a high BTU pro-style range that has the consequences of requiring that expensive high CFM ventilation system and expensive make up air system. They are inseparable from each other once the choice of cooking appliance is made. It is a package requirement, even though most appliance store salesmen will never discuss that need due to their fear of losing a sale. Instead, they should focus on gaining a sale if they approach the needs for the vent and MUA with the customer. Ventahood or Broan are both good choices. But you need to get with your HVAC specialist to discuss that MUA system. That has to do with climate, local codes that are possible stricter than national codes, and several other details, in addition to the hood power.