Q&A Forum http://www.greenbuildingadvisor.com/community/rss en Ventilation Baffles over Lean-to? http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-and-durability/105822/ventilation-baffles-over-lean <p>My father is building a detached garage, and we are planning to put insulation in the ceiling within the next couple weeks. I know that we will need ventilation baffles on one side where the roof meets the walls. But on the other side, the roof has a lower slope and forms a lean-to. When I talked with the builder today, he said that we don't need to install ventilation baffles on that side, as there is adequate space between where the top of the insulation will be and the rafters. Can I trust his judgment?</p> <p>Thanks,<br /> Dylan</p> http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-and-durability/105822/ventilation-baffles-over-lean#comments Energy efficiency and durability Fri, 20 Jul 2018 21:50:55 +0000 Dylan Hillman 105822 at http://www.greenbuildingadvisor.com Hybrid insulation: rockwool + foam board (and canned foam for airtightness and extra R-value) http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-and-durability/105821/hybrid-insulation-rockwool-foam-board-and-ca <p>This my first home, very hand have done remodels and stuff before. I wanted to use spray foam but it is out of the question cost wise. I have a 1900 house with plaster. I will be going room by room removing plaster to wire, insulate, drywall and replace windows. I have not found a lot of info on making a home air tight yet. So here is 2 plans not sure how they work work out:</p> <p>Note 1 The plaster wall should give me 4-4.5 inch of stud bay depth. </p> <p>Note 2 will be pulling down vinyl siding to put up 1 inch r5 foam board outside, then hopefully reusing siding.</p> <p>Plan 1:</p> <p><a href="http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-and-durability/105821/hybrid-insulation-rockwool-foam-board-and-ca" target="_blank">read more</a></p> http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-and-durability/105821/hybrid-insulation-rockwool-foam-board-and-ca#comments Energy efficiency and durability Fri, 20 Jul 2018 20:28:38 +0000 NewHomeOwner95 105821 at http://www.greenbuildingadvisor.com Load calcs and action plan http://www.greenbuildingadvisor.com/community/forum/general-questions/105819/load-calcs-and-action-plan <p>We have just received our initial load calcs, as we plan to upgrade HVAC from oil to high efficiency heat pump. We are in CZ4.</p> <p><a href="http://www.greenbuildingadvisor.com/community/forum/general-questions/105819/load-calcs-and-action-plan" target="_blank">read more</a></p> http://www.greenbuildingadvisor.com/community/forum/general-questions/105819/load-calcs-and-action-plan#comments General questions Fri, 20 Jul 2018 12:50:39 +0000 FrankFulton 105819 at http://www.greenbuildingadvisor.com Thoughts on negative pressure after balancing an Venmar X24ERV? http://www.greenbuildingadvisor.com/community/forum/mechanicals/105818/thoughts-negative-pressure-after-balancing-venmar-x24erv <p>For those of you who have read my blog, this is a question about my HRV installation. I have a x24ERV from venmar.<br /> Like most ventilators, the fan tables with the unit provide a way to measure air flow across the core to facilitate balancing fresh and stale air flows.<br /> I have attempted balancing using a digital differential manometer with funny results. I can easily balance the machine within 5%.<br /> I have an anemometer and a home built hood and have measured the air flows from the rooms and verified that they are close to the air flows measured across the core.</p> <p><a href="http://www.greenbuildingadvisor.com/community/forum/mechanicals/105818/thoughts-negative-pressure-after-balancing-venmar-x24erv" target="_blank">read more</a></p> http://www.greenbuildingadvisor.com/community/forum/mechanicals/105818/thoughts-negative-pressure-after-balancing-venmar-x24erv#comments Mechanicals Fri, 20 Jul 2018 12:49:21 +0000 David Goodyear 105818 at http://www.greenbuildingadvisor.com Is it necessary to insulate the ground in a Zone 5B crawlspace? http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-and-durability/105815/it-necessary-insulate-ground-zone-5b-crawlsp <p>Small, 192 sf building with a ventilated crawl space, zone 5b, Central Oregon, ground freezes in the winter. My plan is to seal vents and convert it to a conditioned space using rigid foam - R15 on walls, R20 at the rim joist. No cavity insulation between floor joists. Building has 24" stemwalls and a 6" tall footing. The footing and stemwall were poured flush with each other on the interior, and the dirt floor inside is level with the bottom of the footing.</p> <p><a href="http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-and-durability/105815/it-necessary-insulate-ground-zone-5b-crawlsp" target="_blank">read more</a></p> http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-and-durability/105815/it-necessary-insulate-ground-zone-5b-crawlsp#comments Energy efficiency and durability Fri, 20 Jul 2018 00:38:32 +0000 KevinEJ 105815 at http://www.greenbuildingadvisor.com How should I insulate my roof? http://www.greenbuildingadvisor.com/community/forum/general-questions/105814/how-should-i-insulate-my-roof <p>I bought a house in Northeast Ohio which I am hoping to retrofit. Here is a link to some pictures of the house:</p> <p><a href="https://www.zillow.com/homedetails/5410-Lockwood-Rd-Madison-OH-44057/34456814_zpid/" title="https://www.zillow.com/homedetails/5410-Lockwood-Rd-Madison-OH-44057/34456814_zpid/" rel="nofollow">https://www.zillow.com/homedetails/5410-Lockwood-Rd-Madison-OH-44057/344...</a></p> <p>I am using </p> <p><a href="http://www.cornerstonehomeconstruction.com/" title="http://www.cornerstonehomeconstruction.com/" rel="nofollow">http://www.cornerstonehomeconstruction.com/</a> </p> <p>as the general contractor. They do have experience with DER and building new homes which have met the passive house standard.</p> <p>I am going to be doing my retrofit in stages as I save money. Currently, I have enough money saved to redo the roof.</p> <p><a href="http://www.greenbuildingadvisor.com/community/forum/general-questions/105814/how-should-i-insulate-my-roof" target="_blank">read more</a></p> http://www.greenbuildingadvisor.com/community/forum/general-questions/105814/how-should-i-insulate-my-roof#comments General questions Thu, 19 Jul 2018 21:23:56 +0000 Steven_Gubkin 105814 at http://www.greenbuildingadvisor.com Insulating conventional corner http://www.greenbuildingadvisor.com/community/forum/gba-pro-help/105812/insulating-conventional-corner <p>I’m converting our 2car attached garage into conditioned shop. I’ve began weather sealing and am trying to decide what to do with the conventional corners box corners. Not sure what the proper term is for that but I’m referring to how the last and first stud in a corner of two perpendicular walls meet so that they essentially form a post, or a situation where there is an empty cavity facing the exterior and now way to access it from the interior. </p> <p>I’m thinking I should:<br /> -cut out one stud out and toenail it back to the sheathing so it’s oriented like a “California corner”?</p> <p><a href="http://www.greenbuildingadvisor.com/community/forum/gba-pro-help/105812/insulating-conventional-corner" target="_blank">read more</a></p> http://www.greenbuildingadvisor.com/community/forum/gba-pro-help/105812/insulating-conventional-corner#comments GBA Pro help Thu, 19 Jul 2018 18:05:32 +0000 kevek101 105812 at http://www.greenbuildingadvisor.com Tape widths http://www.greenbuildingadvisor.com/community/forum/general-questions/105810/tape-widths <p>I'm doing some air sealing on plywood seams using 3 m flashing tape. Is there some standard range of what the width of the tape should be. Like wall to ceiling edge seam or floor to wall edge seam or even just the seams between two sheets of plywood. How does a person determine an appropriate width to use? Thanks</p> http://www.greenbuildingadvisor.com/community/forum/general-questions/105810/tape-widths#comments General questions Thu, 19 Jul 2018 00:29:11 +0000 Smokey059 105810 at http://www.greenbuildingadvisor.com Basement walls: Encapsulate with plastic sheet, tied to interior French drain? http://www.greenbuildingadvisor.com/community/forum/green-building-techniques/105808/basement-walls-encapsulate-plastic-sheet-tied-inter <p>Hello brain-trust,<br /> Wondering everyone's thoughts on this approach.<br /> I'll be installing a full interior french drain in the basement (1960 house), to fix seepage around the cove joint. wondering if i should install "wall encapsulation" at the same time. Attached image shows the idea. basically, a sheet of poly is glued/fastened near the top of the foundation wall, and is run all the way down the wall, into the newly installed drainage system. in theory, and moisture behind this sheet should run down into the french drain--always staying out of the basement.</p> <p><a href="http://www.greenbuildingadvisor.com/community/forum/green-building-techniques/105808/basement-walls-encapsulate-plastic-sheet-tied-inter" target="_blank">read more</a></p> http://www.greenbuildingadvisor.com/community/forum/green-building-techniques/105808/basement-walls-encapsulate-plastic-sheet-tied-inter#comments Green building techniques Wed, 18 Jul 2018 20:19:05 +0000 corry daus 105808 at http://www.greenbuildingadvisor.com Geotextile under gravel below slab? http://www.greenbuildingadvisor.com/community/forum/general-questions/105805/geotextile-under-gravel-below-slab <p>Hello all, I am building a slab on grade structure using the techniques outlined on this and other reputable sites to prevent moisture and soil gas infiltration through the slab - i.e. 4" of washed, crushed stone on compacted soil, with poly vapor barrier on top of stone and immediately under concrete slab.</p> <p><a href="http://www.greenbuildingadvisor.com/community/forum/general-questions/105805/geotextile-under-gravel-below-slab" target="_blank">read more</a></p> http://www.greenbuildingadvisor.com/community/forum/general-questions/105805/geotextile-under-gravel-below-slab#comments General questions Wed, 18 Jul 2018 18:55:37 +0000 Chris Johns 105805 at http://www.greenbuildingadvisor.com