Planning your ADU

Today we’ll talk about planning your ADU project. For reference, it takes us about 4 to 5 months to build an ADU, from the time we get the building permit. Let’s talk about the steps to building an ADU from the beginning.

The first thing is figuring out how much ADU can you build and what should be the size of your ADU. That is determined by your city requirements, required set backs on the property, your city’s ADU rules, etc. In addition, you have to think about your budget. Your soft costs, which consists of engineering fees, architect fees, and city costs, as well as hard costs – the construction costs.

Basically, the soft costs are the fees and costs you have to pay, before I hammer my first nail. So the total costs are a combination of your soft costs and hard costs. The key factors that determine your hard costs are: 1. Foundation- what type of foundation you are using 2. Framing- which is determined by the size of the ADU 3. Utility connections – You need four connections to the ADU: electricity, water, sewer.

The additional costs are for items we need during construction: porta potties, fences, construction equipment, etc. as well as items inside of the ADU: appliances, instant hot water heater, HVAC, finishes, appliances and landscaping, etc. All these items add to the hard cost of the ADU.

What I always tell my clients is this: consider the fixed costs regardless of the square footage of the ADU. You need appliances, instant hot water system HVAC, trenches dug, so figure out the biggest ADU you can build – you can amortize those fixed cost over the size of the ADU. So the larger ADU is actually cheaper. The most expensive part of the ADU is actually the first 400 square feet because you have to make all those connections, build your foundation, and pay the fixed costs. Beyond these fixed costs, your ADU gets cheaper on a dollar per square foot basis, because you’re basically adding framing, flooring, roof and drywall.

Let’s talk about one more thing that’s important. People build ADU’s for various needs – here are some common reasons why people build ADUs: A lot of people, especially in the Bay Area are building ADU’s as rentals. What’s important is the number of bedrooms: two bedrooms vs. a single bedroom will attract better rent. Also, for rental units, privacy comes into play. Do you want your renters looking into your backyard or looking into your living room? Where should the entrance be? And, of course, you want to have durable finishes. What type of counter tops? what type of floors? Is a carpet floor as durable as a wood floor, no it is not. So all those things have to be considered, feel free to contact us, we’ll sort out all those details for you.

The other aspect is, is the ADU being built for older parents or in-laws? What are the things you have to look out for? Maybe full ADA compliance or partial compliance. Having the doors wider, have benches and handles in the shower, etc. Also consider their lifestyle choices – maybe they like to do gardening or cooking. If the ADU is being built for a future home, some people even talk about aging in their lot and then moving into their ADU, and giving their home to their children or renters. The design or style of the ADU, storage space, lifestyle choices, all these things can be factored into the design of the ADU.

Another thing is building an ADU for their children as they are starting their career. Then you will want to think about privacy, access, durable finishes, extra sleeping space, etc. You can factor these things when you are designing and building the ADU. Finally, some people build ADU’s before they sell their home, so they can benefit from the increased equity from the additional square footage. You want to look at materials that are still attractive but not too expensive. You want to make it look pretty and maybe do some landscaping outside. So those are the factors you want to consider if want to build an ADU before you sell the primary home.

With that, we have gone over planning your ADU project and how you can optimize your ADU based on your needs. Contact us if you have any questions.

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