backyard cottage, a budget primer

Your custom-designed, backyard cottage is a terrific idea that costs more than a high end auto. To shed light, let’s review key budget areas and some choices together.

Susan's cottage has a 247 sq. ft. first floor and 176 sq. ft. loft. It's built in her San Francisco area backyard. (New Avenue)

Susan’s cottage has a 247 sq. ft. first floor and 176 sq. ft. loft. It’s built in her San Francisco area backyard. (New Avenue)

According to New Avenue Homes, a custom one-bedroom, 360 sq. ft. cottage will cost $147,000 including its design and permitting ($26k), construction ($106k) and project management ($15k). Yet we noticed a few places to save costs:

  • Buy existing house plans, making minor changes – $15k
  • Use pilings instead of a concrete foundation – $5k or more
  • Take over your bidding, oversight & administration – $15k
  • If willing, run your own project in lieu of a manager – $15k

Excluding project management, there are 13 different building steps and plenty of details to consider in your budget. Make sure you have plenty of room to make changes as well.

Build preparations

  • Design & permits – $25k, with $18k for architect/engineer hours, $6.5k for municipal permits and $2.5k for a site survey.
  • Bidding, oversight & admin – $6k for billing, change orders, meetings.
  • General contractor mobilization – $4k for site, toilets, cleanups.
  • Demolition and remediation – $0.6k demolition if needed.
  • Site work & earthwork – $7k for digging foundation, utility trenches.
  • Foundation & concrete – $12k for foundation construction.

Materials and installation

  • Framing & carpentry – $22k for all framing, interior work, cabinets.
  • Insulation & moisture protection – $13k for siding, roofing, insulation.
  • Windows & doors – $6k for four doors, four windows, one skylight.
  • Finishes – $11k for painting, walls, floors (appliances extra, by owner).
  • Plumbing – $16k for gas, sewer, water, all bathroom, sinks.
  • Heating, ventilation & air conditioning – $4k for gas unit, ducts, vents.
  • Electrical – $5k for wiring, panels (fixtures extra, by owner).

help me with municipal approvals

One of the gotcha steps of building a tiny or small house is reviewing building plans with your county and city officials — and getting those plans approved before construction begins.

If you aren’t a professional, then maybe it’s time to seek help. Here are four options which rely on external suppliers.

1. Architect: Arrange for an architect to handle plans, hire reliable builders, obtain approvals and permits, and make sure you are happy. You are paying for all the professional advice and have an advocate to make changes required by municipalities. It’s a sweet and pricey option.

ARCHITECT: Imagine living somewhere special and getting this modern home approved. It's an exposed concrete cube tucked naturally into the mountainside. From architect Lischer Partner Architekten Planer. (Ferienhaus Vitznau)

ARCHITECT: Imagine living somewhere special and getting this modern home approved. It’s an exposed concrete cube tucked naturally into the mountainside. From architect Lischer Partner Architekten Planer. (Ferienhaus Vitznau)

2. Builder: Buy existing plans from an architect directly or third party like Houseplans, with a materials list included. When you hire a builder/general contractor, they are supposed to get approvals and permits. If you need to make plan changes, then seek out an architect, designer or plan provider.

BUILDER: This single-level deck house received Fine Homebuilding Magazine's Small Home of 2013 Award for "its shared spaces and connections to the outdoors." Building plans for the 800 sq. ft. home are available for sale. (Houseplans.com)

BUILDER: This single-level deck house received Fine Homebuilding Magazine’s Small Home of 2013 Award for “its shared spaces and connections to the outdoors.” Building plans for the 800 sq. ft. home are available for sale. (Houseplans.com)

3. Prefab Supplier: You may order a prefab house “kit” and hire a builder. Yet many suppliers offer construction services which alleviate stress. Kanga Systems builds your house, ships it, places it on your site and finishes set-up. For about $10k, they will obtain approvals and permits beforehand.

PRE-FAB SUPPLIER: A welcoming, country style is seen in this tiny house. It features well proportioned windows, doors and an open front porch. The board and batten siding makes it feel authentic. Kanga's house measures 168 sq. ft. (Kanga Studio)

PRE-FAB SUPPLIER: A welcoming, country style is seen in this tiny house. It features well proportioned windows, doors and an open front porch. The board and batten siding makes it feel authentic. Kanga’s house measures 168 sq. ft. (Kanga Studio)

4. Shed Supplier: Backyard sheds provide simple, extra space. As tiny structures without major plumbing, you shouldn’t run into permit issues. There are six ways to buy them, from architects to near-DIY projects. One long-standing supplier is Modern-Shed, which delivers and installs modern escapes on site.

SHED SUPPLIER: In Seattle, a felt artisan was fed up with working in her family kitchen and ordered this craft shed which fits perfectly. she selected the nice red color and added the deck. (Modern-Shed)

SHED SUPPLIER: In Seattle, a felt artisan was fed up with working in her family kitchen and ordered this craft shed which fits perfectly. She selected the nice red color and added the deck. (Modern-Shed)

Changes afoot on the tiny and small house front

Be prepared for some house rejections from your municipality, even with help. Your dream place may not be large enough, have the right proportions for space use, or exclude appropriate egress. It’s possible that your foundation or materials aren’t up to snuff. Perhaps the power, water and sewage hook-ups won’t be approved yet. We can’t predict the objections, and sigh with you.

It’s okay if your first plans don’t fly. If you aim to build under 400 sq. ft., then upsize a little bit. We do need to share how a woman moved to Hawaii, bought land and received approvals to build a garage and main home. So far, she has built on the garage pad and lives in that sweet tiny house. Her main house will be constructed and rented out — though she isn’t in a hurry.

Or follow the wheels of tiny housers who have preceded you. If you need and want a full house with comforts and will be using it part-time, then consider buying a trailer-based beauty from 100-200 square feet. In this case, you go to the DMV and get a license instead.

By getting approvals for and living legally in YOUR tiny or small house, you are contributing to the greater good too. Municipalities have opened up their requirements, especially for secondary dwelling units and for trailer house uses. It’s only a matter of time for changes to spread from Portland (OR) and Austin (TX) to other U.S. cities.