Permit process for home additions

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Permit process for home additions

Before you start working on architectural plans for your home addition project, you need to realize your budget. This is a tough task for someone  who never had any experience with construction. If you looking for someone to give you an estimate, it will be a good idea to talk to experienced General contractors first or with Design-build companies, those who involved in home addition  or new home construction projects all the time.  “General Contractor” – means a licensed person or a company representative, who involved in estimating and contract signing. The guy with the truck, tools and knowledge how to use them, working in site for contractor, building even large structures using his own hands – is not a contractor, he’s a professional laborer or handyman and in 99% cases doesn’t have any knowledge of construction budget. Contractors who mostly involved  in commercial construction or public works, or simple remodeling, like kitchens and baths, painters, plumbers and other tradesman’s are not good option either. Looking on some quotes of General Contractors who involved only in residential basic remodeling projects and currently bidding on home addition or new home construction project, sometime make me wonder what they were thinking before giving their estimate to customer. In some cases bids are overestimated by a good amount of $, but in most cases bids are underestimated and after looking on final number of underestimated bid, client doesn’t want to study other bids, he likes the number he sees  and it’s hard to change his mind. Later, of course job goes over budget and that happens every day, like an epidemy, almost on every project I know about; once you started construction it must be finished, there is no simple way back, so you must constantly add funds and increase the budget.

Final amount of $ spend on a job is your real budget that was supposed to be setup in a first place. About how to calculate a budget right, check back soon with my blog.

So, why start with Contractors first, rather than with Architect? Architect or Designer can design anything you really like, propose home of you dream, especially when interior design takes place with professional photo like renderings, however you wont be able to enjoy it without some features that you cannot afford if you don’t know how much the whole thing cost. And Designers can’t tell exactly how much finished job will cost, even if price list for some finish materials in front of them, as they don’t know how much labor involved in installation, unless they have contractor on board, who can help price it beforehand.  Contractors or design-build companies can show you some good examples of completed projects and tell you what was the entire budget without spending much time on estimate. It is easier for a person to understand what his project will cost approximately when he see some examples and able to compare.



Now I will describe the entire process of obtaining permits from the city. It is a simple process once you know how to do it, however rules varies in different cities and you need to check with building or planning dept.  every time when submitting a new project, as something may have changed.

  • First, get exact measurements of existing house and all other accessory structures on site and draft in scale.

  • Prepare a site plan, showing location of all structures currently on site, calculate lot size and also square footage of the existing structures to understand how many square feet you can actually add.

  • Based on these  numbers see what can you do within maximum allowed square footage, which way to expand, what is your lot setback, what is the height restriction, 2nd floor setback, daylight plane, how is the majority of the houses on a street looks like and who are your neighbors. Don’t forget about privacy issues either. Note that 2nd floor additions are more complex in preparation and  besides planning approval require architectural committee approval and/or neighbors review of a project and approval prior to plans approval in planning department. So it good to know your closest neighbors and keep good relationship with them, however at some projects  neighbor is an apartment complex and that’s exactly where you gonna get into tons paperwork.

  • Now when you know what are the options,  you need to understand what you can afford. I will not explain in details in this post how to calculate budget yourself, that will be completely separate theme for a separate post. So let’s assume you figured that out and now ready to move forward with the plans.

Constant meetings with the designer and changing things will not actually help much, but rather make entire process slow down. If you don’t feel that you understand terminology, calculations and don’t know how to read plans, just simply  trust the designer. Ask him to explain what you don’t understand in simple words, don’t act like you do understand if you really not. Just keep an eye on a progress and make sure that you still in budget and always ask what are the pros and cons for each option that is proposed by designer. If you don’t know how to sketch, or draw in scale, simply make a list of options and features you’d like to have and put it on paper and make it a check list for the designer.  Next steps for the plans drafting is:

  • Determine windows and exterior doors locations, understand egress.

  • New floor plan options: bathrooms/kitchen location, ceiling height

  • Heating and cooling equipment options.

  • Electrical/lighting plan. On this task  is a good idea to talk to lighting specialist to understand size and diameter of the lights and overall power consumption. I know, many of you will do completely opposite thing, just through some light icons on a plan and try to figure out lighting when construction get closer to actually install lights, but it’s actually not right thing to do, as later you really won’t have time to think about it and you will delay the project completion.

  • Discussing interior doors location and dimensions. Understand cost of door slabs and frame, solid or hollow.

  • Recessed, vaulted ceiling depth and location.

  • Architectural details and custom features like crown mouldings and door/window casings and their size.

  • Discussing exterior finishes.

  • Exterior lighting options.

  • Basic landscaping, walkways and driveway options.

  • Public utilities options and problems that may arise as new electrical service these days for most projects must go underground.

Preparation of final set of architectural plans, elevations, electrical plan, site plan and landscaping plan.

  • Final review of all pages of complete architectural set and get ready for the printout.

  • Full set of pages shall contain the following:

    • Cover page with area calculations and project information
    • Existing site plan
    • Existing demolition floor plan and roof plan
    • Existing elevations
    • New site plan
    • New floor plans
    • New elevations
    • New roof plan
    • Electrical/mechanical plan
    • 2 section cuts of the new building
    • Exterior doors and windows schedule
    • Exterior finish materials description
    • If separate formal landscaping plan is asked by the city officials, then you need to hire a landscaper and work out a plan to propose to the city. Not all designers will be drafting landscaping plan for the project, because it not always a requirement . Most likely it will be an extra cost to attach formal landscaping plan to the final set of architectural drawings.

After city planning department approves the plans, architectural plans being sent to structural engineer to work on produce structural drawings and calculation.

At the same time plans may be sent to energy estimator to calculate Title 24 and prepare, if necessary, Green Building Check list.

It is possible that you can start working on engineering plans before getting architectural plans approved to save time, if you see that  process go smooth and there is no additional comments from the city and you not making any last-minute changes.

Documentation submittal to building department.

On small projects plans are good with just architectural plans, engineering made, and basic architectural site plan. Some cities does not require land survey for small additions, however may require official letter from surveyor prior to calling foundation inspection. Prior or after building department submittals, you will be able to determine if any of the following additional items are needed to successfully obtain  a building permit:

  • Civil engineering (some cities require drainage and grading plan and normally for small projects it’s not required)

  • Soil Engineering (Most cities require it only for new house construction, however it may be necessary for large additions over 1000 sq.ft. or in areas with in Seismic hazard zones)

  • If the addition and existing house remodeling combined are over 50% of the existing house by floor area, then project is subject for Fire sprinklers installation. Before Fire sprinkler contractor cant prepare their calculations and additional plan to attach to a full set of drawings, you need to provide them with water flow test results. Flow test results can be obtained from a local water company. Water company water flow test are not free. They charge between $400 to $1400, unless they have previously made tests, then you can get them free of charge. Fire sprinkler design is free of charge only if contract is signed beforehand.

  • Roof truss calculations if you using roof trusses. Truss company will also provide calcs and plan for free only if contract for truss production is signed. Roof trusses are the cheapest way to go and unlike old trusses, modern truss companies  can design attic storage spaces, spots for furnaces, access doors, skylights, tray type ceilings, vaulted ceilings etc.

  • In some cities you may be asked for a permit from Sanitation District prior to building permit issuance. In this case they will require you to either install a new cleanout within a property easement or completely replace a sewer line all the way to the main line at the street. Watch out! That can get very expensive, as this work requires licensed class A engineering contractor working on a public street.

  • In cities without sewer line available (exmpl. Los Altos Hills) you will be required to get an approval from your county Environmental and Health department. If any bedrooms or bathrooms proposed for the project – get ready. That will be really expensive, as county will require new leach field installed, plus reserve extra area for future leach trenches in case primary leach field will fail. That area at a minimum must be equal to what you have now plus additional area. (example: Existing leach field has 200 l.ft. of trenching and  you adding 1 bathroom and 1 bedroom, then most likely requirement will be to add 400′ of new primary leach trenches, plus reserve area to allow future installation of another 400′ of trenching if primary fails) To provide calculations and a plan, good leach field contractor needs to be hired. He will inspect existing septic system, complete soil percolation test with recorder test measurements and prepare plan to propose new trenching.  Just a ballpark estimate: altogether you looking at approximately $50,000.oo including installation of new leach trench. Up front charges for percolation test, inspection and calcs – around $10K

  • After all necessary documentation is submitted, all revisions are made (if any) and building permit is ready to be picked up, then you will need:

    • Pay school fees if the addition is over 500 sq.ft. It is required to pay your local elementary and high school and a fee is about $1.25 to $1.50/sq.ft. Information about what exact school district you are in can be obtained in a city building department.
    • In some cities prior to building permit issuance, city may require you to obtain a demolition permit first and then building permit may be issued only when demolition permit is signed-off on final inspection.
    • To pass final inspection for demolition inspection we need to have the following:
      • In SF Bay Area it is required to obtain so called “Air pollution” permit.
      • Fence all trees on site as it was shown in site plan or noted by plan checker in a city.
      • Disconnect gas and electrical and have you local gas and electrical company submit a letter to the city with confirmation.
      • Normally another permit from the city needs to be obtained if gas and electrical are subject to disconnect – A temporary power pole permit. Because you will need power on site during construction. So simply work with the energy company so they can reconnect power to temporary power pole at the same time when they are on site to disconnect the overhead line from existing main panel. To get that done, you now need to get final inspection on power pole installation first, when inspection is complete, city inspector will fax or email Energy Company signed  meter release form and they can now schedule an connect/disconnect. I know it sounds very confusing, but it’s actually very simple once you get it understood.
      • When Electric power connect/disconnect is complete then Demolition permit can be finalized.
      • And then building permit fees may be paid and permit picked up.
      • Next phase is construction

If you wish to receive complete and detailed checklist for planning and building department permit obtaining  process. Please contact us with our contact form.





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