Adding living space to your existing home
So you’ve been looking at that open utility basement and thinking it would be a great space for an extra bedroom, bathroom and new recreation room. You aren’t the only one with those ideas. This is one of the most common major projects homeowners dive into. Turning that space into useable living space will probably also be cheaper than buying a new, bigger home or building an addition.
Almost anyone can turn a raw space into useable living space. Not everyone can do it safely, efficiently and Code compliant. There are numerous important factors that need to be considered with such a rehab.
If you live in the City of Chicago, you will need to hire contractors for a lot of the work but not all. Rules vary in the surrounding suburbs. Depending on your municipality and the classification of your building, you may be able to do more of the project yourself, as a DIY weekend warrior. If your property is a single family home, licensing tends to be more lenient. If your building is a small owner occupied multi-unit, say a 2 or 3 flat, there are typically more requirements.
There are significant factors to consider when remodeling an open basement. The following pages outline some of the common construction issues that come up in a basement rehab.
For those of you go-getters out there who don’t care about building codes or construction standards … You will when it comes re-sale time or when a municipal inspector comes knocking. Those 2 extra bedrooms may not be compliant. You won’t be able to add them on your listing sheet. And there can be substantial for removal of non-compliant construction.
Remember, proper construction keeps your family safer. Please plan your project properly.
There are two main factors to consider before starting a basement build-out. ‘Is the basement water tight’ and what is the ceiling height.
If this is a new home, I suggest you wait at least one full year before proceeding with a basement rehab. This will allow you to see how the foundation walls perform throughout all four seasons. People have bought homes in the fall, started a basement remodel right away and come spring rains find out that the basement takes in water. It does not take complete flooding to substantially destroy a new basement rehab. It is possible to do IR scans of walls to investigate possible water intrusion.
If you have been in the home for a few years, then hopefully you will have an understanding of how your foundation walls perform. Any seepage problems should be corrected prior to proceeding with a rehab. Even a small amount of seepage can create much more trouble in a remodeled basement than ever occurred while the basement was open. This happens for two main reasons. 1) Moisture gets trapped within walls and cannot just evaporate; and 2) Moisture comes in contact with organic materials such as drywall and lumber which usually causes contamination and mold issues.
BASEMENT build-out considerations
Basement ceiling height: Typically you will need at least 7’ to 7’-6” minimum finished ceiling height in order for the space to count as compliant occupancy square footage. If the ceiling height is less than 7’ the space is usually only counted as utility or storage space, regardless of how much money you spent to make it pretty. One of the biggest problems with low ceiling height comes when owners think they have added 1 or 2 bedrooms. Without sufficient ceiling height, it isn’t considered a compliant bedroom.
Egress: Depending on size you will need one or two means of egress from the basement. Depending on various factors, suburbs may also require an approved escape window assembly.
Flooring: Natural, real wood flooring planks are not recommended for below grade installations in most cases. This is due to the potential moisture levels. Natural wood floors can move or buckle too much depending on conditions. If you want wood floors consider using engineered wood flooring.
Open floor drains: Older basements typically have sloped cement floors and floor drains. If you plan to install finished flooring, I suggest you hire a plumber to assess and cap or extend the drains. Leaving the drains as-is and just covering them up may not be the most prudent option.
Light and Ventilation: Basement rooms will need properly sized operable windows. A glass block window with a tiny louver vent is typically not sufficient.
Insulation: There are two types of insulation to consider during a basement build-out; exterior wall insulation and ceiling insulation. Exterior wall insulation seems rather obvious. Ceiling insulation unfortunately is often overlooked until it is too late. Insulating the ceiling can reduce noise from above. It can be quite annoying to spend a lot of money on a basement rehab and then clearly hear others walking and talking on the 1st floor. Sound insulation can be accomplished with various sound boards or batts.
Drywall: Due to higher humidity levels in some basements you may want to consider installing moisture resistant drywall (greenboard) along the bottom of walls in the basement.
ADDITIONAL build out considerations
- Plans: Chicago and suburbs such as Evanston or Wilmette will most likely require architectural plans for a basement rehab. Other suburbs may only require drawings. Check with your local municipality.
- Permits: Chicago and most, if not all, suburbs will require a construction permit. Costs vary. Chicago has a permit fee calculator on their website. At least some suburbs have permit fees listed on their websites. Permit fees are typically based on various factors.
- Costs for re-routing existing electrical should be factored into your budget.
- Plumbing vent stacks and floor drains may need to be extended or re-routed. This would entail excavation, plumbing and concrete work.
- If adding a bathroom, the vent fan should be exhausted to the exterior, NOT to a joist cavity or the attic.
- Most home heating systems are not sufficiently sized to handle the extra space of a complete build-out. You will likely need to add a new heating and cooling system. It is possible to upgrade an existing system to save money. The cost of a complete new system is substantially higher. A separate system for the basement space will give you better control and comfort levels though. New ductwork can be hidden in soffits along beams or joist cavities.
- Inspectors: Whether you get a permit or not, a municipal inspector may come knocking. If so, be nice, be polite, say Yes Sir and Thank you Sir; even if you think he is being a pain in your side. A municipal inspector can be very helpful and informative. If you make him or her mad, they can make your project hell. So be nice. Accurate Inspections can provide construction inspections throughout the project. This can help keep contractors inline and reduce construction issues. Costs are reasonable.
- A note on insulation: “Stuffing” insulation into a smaller cavity than it is rated for does not increase the R-value. This can decrease the R-value depending on product used.
Obviously this article cannot cover all the factors you should consider when planning this project. There will be variables based on existing construction components of your home, your goals and local Codes.
This article should only be considered a primer towards helping you understand some of the issues you are likely to encounter. These projects are complex but can be simple enough with proper planning. AIC can provide an evaluation report and helpful information that you can use to begin the process. The information can also serve as a valuable resource when interviewing contractors for the job.
We hope this article is helpful. Feel free to give us a call to discuss your project. Accurate Inspections serves clients throughout the Chicagoland area.