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sideout
1.5 story house and insulation

I have a 1.5 story house and when i purchased it the upstairs was unfinished. It had blown insulation in the rafters and soffitt vents. I have since finished the room with a bedroom, closet and bathroom upstairs. The room is extremely cold. I have two half walls that run the length of the room on each side being its a 1.5 story. Each side does have a crawl space that I do have access too. I really had a couple questions. I insulated the half walls and the angle that leads to the ceiling along with the ceiling. I am sure that cuts off the air flow from the soffitt vents to the roof vent. Does that matter? And what else should I be doing to better insulate the crawl space? Or really all the spaces? I know I need more insulation but I was concerned with affecting the venting of the areas. I didnt want mold or anything else growing upstairs.

Blue RidgeParkway
Re: 1.5 story house and insulation
sideout wrote:

I have a 1.5 story house and when i purchased it the upstairs was unfinished. It had blown insulation in the rafters and soffitt vents. I have since finished the room with a bedroom, closet and bathroom upstairs. The room is extremely cold. I have two half walls that run the length of the room on each side being its a 1.5 story. Each side does have a crawl space that I do have access too. I really had a couple questions. I insulated the half walls and the angle that leads to the ceiling along with the ceiling. I am sure that cuts off the air flow from the soffitt vents to the roof vent. Does that matter? And what else should I be doing to better insulate the crawl space? Or really all the spaces? I know I need more insulation but I was concerned with affecting the venting of the areas. I didnt want mold or anything else growing upstairs.

Yes it matters.
You confuse the issue using the term crawl space twice and describing attic space in between.

If you are referring to the space above the first story (First story attic) and below the roof - that space behind the 2nd story's walls and between those walls and the roof deck that is an attic space (even if it is so short in height you have to crawl to get in there).

If you are referring to a space within the foundation and below the structural first floor, which is too short in depth to be a basement, that is generally referred to as a crawl space. Although you would have to crawl to get around in either location, just as you might if you had a pier and beam home on short piers and even if "skirted" still not a true crawl space, generally a "crawl space" refers to a short statured space within foundational walls and/or footing walls/frost walls.

All three areas mentioned above are insulated differently, all three areas the best methods of how accomplished vary by region (temperature/climate) and home's construction.

If you created a vaulted ceiling area in a converted attic and short circuited the ventillation for the roof deck then yes you most likely should remediate that. From your description I'd also guess you are or will encounter significant moisture/condensation/rot issues as well. If this space was previously not a conditioned space - what provisions did you make regarding HVAC?

There are different approaches (eyebrow vents - which basically look like half a ridge vent slipped in the field of the roofing to intake, baffles, ridge vents, rafter vents, soffit vents, for balloon construction - lower to grade vents, rafter strapping and creating a raised platform type roof over existing roof deck, etc.) depending on your home's construction.

These are questions and issues you should have addressed BEFORE you finished the space, in order to properly convert the previously uninhabital space to habital space, along with many others, for example fire/draft blocking the 1st story ceiling/1st story attic to 2nd story floor/wall/to side attic junction and the 2nd story wall/ceiling/roof/attic junction.

sideout
Re: 1.5 story house and insulation

Let me clarify. The house is a 1.5 story and was built with the intent of being finished upstairs. The HVAC was roughed in by the builder along with the plumbing. The previous owners chose not to finish the upstairs. I have access to all the areas that I need to insulate more or even make changes to. Both sides of the room have access panels so that I can "crawl" into them and also meet local building codes. All my areas have been inspected for code, my biggest issue is that I could add more insulation or make improvements to make the room more comfortable.

bp21901
Re: 1.5 story house and insulation

You should have put air channel baffles against the roof sheathing before putting the insulation on the slanted part of the ceiling. These allow the air from the soffit vents to make its way to the ridge vent. Just to clarify, you mention a roof vent....is it a ridge vent?

Are you not getting any heat from the roughed in HVAC or is it just not enough? Are there return vents also roughed in or just supply vents?

sideout
Re: 1.5 story house and insulation

yes I do have a return vent and im sorry it is a ridge vent not roof vent. I still have access to put in the channel baffles. I was at the home improvement store today and saw a manufacturer instruction sheet on the channel baffles. I am going to buy the plastic ones and install them along with adding more insulation. Would it be ok to staple plastic sheating along the half wall on the inside or would that cause moisture problems.

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