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Unfinished Basement

A

AaronA

Registered User
Joined
Feb 7, 2024
Messages
8
Location
California
Hello,

We purchased a home with an unfinished basement. We are going to keep the basement unfinished due to the ceiling height (around 6 1/2 feet) and the difficulty in putting in an emergency egress.

The city approved plans to replace an existing mini split and redo the electrical, and lighting. The inspector came out and said that we cannot have a permanent heat source and that we may need to remove all but one light and one electrical outlet (the room is around 450 sf).

What are the legally allowed uses of an unfinished basement? Are there any rules on electrical and lighting? I am in California and am having trouble locating anything I can reference.

Thank you for any assistance!
 
If the city approved the plans, the role of the inspector is to inspect to ensure that the installation was performed correctly. His job is not to effectively invalidate the permit you have already obtained. Aside from that, you are replacing an existing mini-split. If it wasn't legal, why did they approve a permit to replace it?

The inspector needs to have cited code sections to fail the inspection.
 
2018 IRC
N1107.2 (R501.2) Existing buildings.
Except as specified in this chapter, this code shall not be used to require the removal, alteration or abandonment of, nor prevent the continued use and maintenance of, an existing building or building system lawfully in existence at the time of adoption of this code.
 
mtlogcabin said:
2018 IRC
N1107.2 (R501.2) Existing buildings.
Except as specified in this chapter, this code shall not be used to require the removal, alteration or abandonment of, nor prevent the continued use and maintenance of, an existing building or building system lawfully in existence at the time of adoption of this code.
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I missed this
AaronA said:
existing mini split a
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Of course we do not know if it was legally existing....
 
Are crawl spaces limited to one outlet and one light? Never heard of such a limit.

Does any code prohibit conditioning crawl spaces? Never heard of that either.
 
R408.3 Unvented crawl space.
Ventilation openings in under-floor spaces specified in Sections R408.1 and R408.2 shall not be required where the following items are provided:

1. Exposed earth is covered with a continuous Class I vapor retarder. Joints of the vapor retarder shall overlap by 6 inches (152 mm) and shall be sealed or taped. The edges of the vapor retarder shall extend not less than 6 inches (152 mm) up the stem wall and shall be attached and sealed to the stem wall or insulation.

2. One of the following is provided for the under-floor space:

2.1. Continuously operated mechanical exhaust ventilation at a rate equal to 1 cubic foot per minute (0.47 L/s) for each 50 square feet (4.7 m2) of crawl space floor area, including an air pathway to the common area (such as a duct or transfer grille), and perimeter walls insulated in accordance with Section N1102.2.11 of this code.

2.2. Conditioned air supply sized to deliver at a rate equal to 1 cubic foot per minute (0.47 L/s) for each 50 square feet (4.7 m2) of under-floor area, including a return air pathway to the common area (such as a duct or transfer grille), and perimeter walls insulated in accordance with Section N1102.2.11 of this code.

2.3. Plenum in existing structures complying with Section M1601.5, if under-floor space is used as a plenum.

2.4. Dehumidification sized to provide 70 pints (33 liters) of moisture removal per day for every 1,000 square feet (93 m2) of crawl space floor area.
 
So mt do you agree that if it isn't a basement it could be a crawlspace and could be conditioned (or has to be if unventilated)? And that the sizes, etc, in your quoted code are minimums?
 
mtlogcabin said:
R408.3 Unvented crawl space.
Ventilation openings in under-floor spaces specified in Sections R408.1 and R408.2 shall not be required where the following items are provided:

1. Exposed earth is covered with a continuous Class I vapor retarder. Joints of the vapor retarder shall overlap by 6 inches (152 mm) and shall be sealed or taped. The edges of the vapor retarder shall extend not less than 6 inches (152 mm) up the stem wall and shall be attached and sealed to the stem wall or insulation.

2. One of the following is provided for the under-floor space:

2.1. Continuously operated mechanical exhaust ventilation at a rate equal to 1 cubic foot per minute (0.47 L/s) for each 50 square feet (4.7 m2) of crawl space floor area, including an air pathway to the common area (such as a duct or transfer grille), and perimeter walls insulated in accordance with Section N1102.2.11 of this code.

2.2. Conditioned air supply sized to deliver at a rate equal to 1 cubic foot per minute (0.47 L/s) for each 50 square feet (4.7 m2) of under-floor area, including a return air pathway to the common area (such as a duct or transfer grille), and perimeter walls insulated in accordance with Section N1102.2.11 of this code.

2.3. Plenum in existing structures complying with Section M1601.5, if under-floor space is used as a plenum.

2.4. Dehumidification sized to provide 70 pints (33 liters) of moisture removal per day for every 1,000 square feet (93 m2) of crawl space floor area.
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Per the OP, it's a mini-split - meaning a ductless system in all likelihood. This section does not apply to the situation at hand.
 
My take on the situation is that the basement shows as unfinished in the city's records, and is even described as such by the OP.

If a mini-split is added (or an existing, non-permitted unit replaced), the basement space may be transitioning from unconditioned to conditioned space. Under IECC/IRC Ch. 11, this constitutes an addition. As an addition, compliance with the energy code is required.

Not indicating that I fully agree with the inspector, but if adding HVAC to an unfinished basement, I would tend to agree that the space is being "finished" and needs to comply with egress, lighting, etc.
 
mtlogcabin said:
R408.3 Unvented crawl space.
Ventilation openings in under-floor spaces specified in Sections R408.1 and R408.2 shall not be required where the following items are provided:

1. Exposed earth is covered with a continuous Class I vapor retarder. Joints of the vapor retarder shall overlap by 6 inches (152 mm) and shall be sealed or taped. The edges of the vapor retarder shall extend not less than 6 inches (152 mm) up the stem wall and shall be attached and sealed to the stem wall or insulation.

2. One of the following is provided for the under-floor space:

2.1. Continuously operated mechanical exhaust ventilation at a rate equal to 1 cubic foot per minute (0.47 L/s) for each 50 square feet (4.7 m2) of crawl space floor area, including an air pathway to the common area (such as a duct or transfer grille), and perimeter walls insulated in accordance with Section N1102.2.11 of this code.

2.2. Conditioned air supply sized to deliver at a rate equal to 1 cubic foot per minute (0.47 L/s) for each 50 square feet (4.7 m2) of under-floor area, including a return air pathway to the common area (such as a duct or transfer grille), and perimeter walls insulated in accordance with Section N1102.2.11 of this code.

2.3. Plenum in existing structures complying with Section M1601.5, if under-floor space is used as a plenum.

2.4. Dehumidification sized to provide 70 pints (33 liters) of moisture removal per day for every 1,000 square feet (93 m2) of crawl space floor area.
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The only thing lacking in the "under-floor space" is furniture. Of course he could make the claim that he's storing furniture under the house... and the rug is to keep the dust down.

Changing a label from basement to crawl space is an insult to an inspector's intelligence. Telling a property owner that he is not allowed to condition an unfinished basement is a violation of the 4th Amendment of the US Constitution.

Oh but wait a minute, what about the energy code? Aren't there rules about conditioning a space that lacks state of the art energy conservation? The people should rise up and declare war on Mother Earth.
 
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Reminds me of a basement where it was cleaned up and the underside of first floor seating was the ceiling and the joists were considered beams. Cleaned and varnished. I think 6-6 is enough for a duct or beam? maybe it's 6-8.
 
Hire an Architect to help with your appeal and Hire an attorney to make sure that the inspector is complying with the law. Consider raising the issue at a City Council meeting.
 
Mark K said:
Hire an Architect to help with your appeal and Hire an attorney to make sure that the inspector is complying with the law.
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Or you might want to save money and just relocate.
 
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Mark K said:
Hire an Architect to help with your appeal and Hire an attorney to make sure that the inspector is complying with the law. Consider raising the issue at a City Council meeting.
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You forgot the engineer.
 
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