Figure 1-23: Vinyl siding nailing guidelines (C) Wiley and Sons, S Bliss Definition of Building Dry-In or Dry-Box Status
What does dry-in mean in construction terminology?

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Definition of building dry-in or dry-box status in construction: what does dry-in mean in building construction or in building construction contract writing. This article offers definitions of building dry in or dry-box status. We list what major construction work items must be complete, what steps must have been taken to protect the building interior from the weather, and we also describe how "dry-in" or "dry box" terms are used in construction & in building construction contracts.

Green links show where you are. © Copyright 2015, All Rights Reserved.

Definition of Building "Dry-In" or "Dry-Box" in the Building Construction Trades

Typar house wrap example (C) Daniel FriedmanDaniel Friedman & Eric Galow

"Dry-In" means that the building shell has been completed sufficiently to keep out wind, rain, or the weather in general, thus assuring that weather-sensitive materials or work can begin indoors without those materials suffering weather damage by rain, wind, snow, etc.

For for high-rise buildings dry-in may on occasion be confined to just that portion of the building where interior work is contemplated.

For any building construction project the responsible architect, engineer, or contractor may specify special temporary building protective measures to achieve temporary dry-in status to permit certain interior work to begin.

The requirement for reaching a dry-in state is set to avoid damage or risk of damage to weather-sensitive materials to be used or installed indoors.

The home shown at left does had not reached dry-in or dry-box status; although the roof has been installed, the housewrap is incomplete, window and door openings are just that - open to the weather. [Click any InspectApedia image to see an enlarged, detailed version.].

This building appears to meet dry box or dry in status (C) Daniel Friedman Eric Galow Galow Homes ConstructionSome builders use the term "dry box" for this weather-proof building status, and include the building foundation, framing, doors, windows, exterior siding and trim, and and the complete roof system. In dry-box or dry-in state, a building can be occupied and its interior finished while safe from weather damage.

At left the home appears to meet dry-in status (we can't see the roof). Actually the contractor, Galow Homes in Poughkeepsie, NY was removing the siding as part of a building renovation project. But if we saw a home under new construction but in this state we'd agree that it appears to be at dry-in condition.

Unfortunately an up-close inspection of this particular home when it was just eight years old found extensive trim rot and leaks into the wall structure due to improperly installed housewrap and omitted door and window top trim or sealants. Had a building inspector observed those details during construction she might denied dry in status until those mistakes were fixed. At SIDING, FIBER CEMENT DEFECTS we describe these leak and rot problems.

Interior work that generally waits until building dry-in or building dry box status includes: building interior wall, ceiling or roof insulation, ceiling and wall and floor coverings and finishes, counters, cabinets, countertops, and probably most electrical wiring and plumbing components & fixtures.

Building interior work involving the installation of weather-sensitive materials (such as insulation or drywall) should not begin before the building has reached dry-in status.

Building Dry Box or Dry In should include at least the following

Dry in status of a home shows house wrap, windows, doors, and flashings installed (C) Daniel FriedmanThe building wall shown at left meets dry-in status: housewrap has been installed, windows & doors are installed, and key flashing or flashing tape details are completed to assure that rain will not enter the walls. Not shown, the roof had been covered with a temporary but reliable waterproof barrier. Photo courtesy of Galow Homes, Poughkeepsie, NY.

  • The structure is complete or if necessary, temporary structural supports may be in place sufficient to permit interior work to proceed in safety. For high rise or other large buildings "structure" may refer to only a floor, wing, or segment of the complete building.
  • The roof sheathing is installed and a roof covering, permanent or suitable, reliable temporary roof waterproof covering is installed.
  • The wall sheathing is installed.
  • Housewrap or equivalent moisture barriers have been properly installed
  • Windows, doors, and other opening coverings (skylights, plumbing vent boots around roof plumbing vent penetrations, exterior wall penetrations for wiring, plumbing, etc.) have been completed or else these openings have not been made, or if they have been made they may be temporarily sealed against the weather.
  • Exterior trim, flashings, caulks, sealants have been installed where these are necessary to assure that the building shell is waterproof, wind proof, or more generally, weatherproof.

Refinement of Building Dry-In Status to Allow for Temporary, Expedient Measures

Vinyl siding blow off New Jersey (C) Daniel FriedmanIn my OPNIION the building dry-in shell must be secure against reasonably expected weather conditions. This means that we don't rely just on plastic loosely stapled over an opening, as plastic may blow-off in a wind / rain storm.

But it also means that the dry-box or dry-in building may not remain dry in the face of unusual events such as hurricanes, tornados, or flooding.

Our photo at left illustrates a building whose finish siding and even some of the building paper installed over the sheathing had blown off.

In some situations where water-sensitive work (insulation, drywall) must begin on a building that has not met the defined dry-in details outlined above, a licensed building professional architect or engineer or perhaps a qualified contractor might design and specify an acceptable temporary exterior covering for the structure to permit interior work to proceed.

Watch out: when proceeding on water-sensitive interior work before a reliable dry-in state has been achieved for the building, even if the temporary provisions are perfectly effective, there may be a risk-window if the temporary exterior waterproofing enclosure has to be removed to permit final building exterior coverings to be installed.

The epitome of this situation is when a roofer does a tear-off, nails plastic tarps over the roof and then waits for dry weather to install the finish roof covering.

Building Construction Contract Use of Building Dry-Box or Dry-In Status

Metal chimney during installation (C) D FriedmanDry-in status has other uses such as to define a point in the making of progress payments during building construction.

Watch out: when using "dry-in" as a construction status to be used to define a point of payment for construction work. In this case building dry in must be defined in sufficient detail to avoid an argument later such as whether or not the installation of finish roofing, finish siding, or even windows and doors were included in the contract. A dry-in construction contract should include a form specifying the details of what permanent or temporary installations shall have been completed.

A review of more than 25 building inspection & building construction textbooks in our library failed to find a single clear definition of building dry-in or dry-box status and not one of the texts even included the term dry-in in the book's index. But the terms building dry-in or dry-box frequently appear in model construction contracts, often referring to a detailed bill of particulars of what dry-in shall entail.

Other sources (ARCOM MasterSpec Section 01 50 00 , ASTM C 840 , GA-216) offer definitions pertinent to "building dry-in": - ARCOM gives this definition of a permanent enclosure:

A. Permanent Enclosure: As determined by Architect, permanent or temporary roofing is complete, insulated, and weather tight; exterior walls are insulated and weather tight; and all openings are closed with permanent construction or substantial temporary closures.

This defines "permanent enclosure", not "dry-in". A permanent enclosure status is past "dry-in" status in that it includes insulation and thus presumably wiring and plumbing that would have been installed prior to insulation.

One could argue that a building specification requiring reaching dry-in status before certain work can proceed is intended to avoid the time, trouble, and costs of weather damage to the building or it interior components. For an example of the other side of the building dry-in coin, see CRAWL SPACE DRYOUT

Building Dry-In vs Finish Wall or Siding Installation Clarified

Shiplap or drop lap vinyl siding profile (C) Carson Dunlop AssociatesReader Question:

Can I install the vinyl siding on my garage apartment project before I install drywall. - M.A. 9/21/2013

The building inspector is concerned that weight of drywall will cause siding to buckle.  9/22/2013

Thank you for the information on vinyl siding installation.  I was not worried about installing the siding it was the building inspectors  concern  that if  the siding was installed prior to hanging the drywall  that the weight of the drywall would cause the siding to buckle. M.A. 9/23/2013 This Q&A was originally discussed at VINYL SIDING INSTALLATION.


Your question is worrisome - as I'm not sure what you are worried about. Exterior siding has nothing to do with interior wall finish materials, except that it would be foolish to install interior drywall, vapor barriers, or insulation in wall cavities before the building exterior is finished sufficient to be completely weather tight.

Drywall is attached to and supported by the building structure not by the vinyl siding.

In proper construction we complete the building shell at least far enough along to make the building waterproof before we would ever consider interior work such as installing insulation and then drywall on walls and ceilings.

Improperly installed housewrap violates a building dry-in definition  (C) Daniel FriedmanThe building may be dry - weatherproof, once the roof is on, wall sheathing is on, house-wrap is on, windows and doors are in place, and probably most exterior trim is in place; at that point the shell should be dry and weatherproof (unless an idiot installed the building housewrap improperly) and both exterior siding and interior work (wiring, plumbing, insulation, drywall) can proceed.

If housewrap is improperly installed (photo at left) a sharp building inspector might notice this defect and refuse to agree that the building has reached dry box status until the mistake is corrected.

At SIDING, FIBER CEMENT DEFECTS we explain that if the upper edge of a lower course or section of housewrap is lapped over rather than under the higher course, water leaking behind the siding will find its way behind the housewrap, increasing chances of water entering the building wall cavity itself.

I suspect there is a serious miscommunication going on between you and the building code compliance inspector

Reader Follow-up:

As I am very limited with computers please excuse my inexperience. I thank you for all the information regarding my 2 story garage apartment project.

I have never thought it was a problem to install the vinyl siding prior to installing the dry wall. It was the building inspectors concern. I would love to get my home sided before winter so that I could start the inside. Can building inspector force me to wait or can I move forward with my vinyl siding installation. Thank you again. - M.A. 10/17/2013


Installing vinyl siding on a building exterior has nothing to do with nor does it interfere with the installation of interior drywall, except that improperly installed house wrap, flashing, sealants, or siding, windows, or doors may cause leaks into the structure and thus could be a source of drywall damage or mold. Beginning at VINYL SIDING INSTALLATION we describe vinyl siding choices and installation procedures

Can the building inspector stop a construction project? Absolutely!

If by building inspector you mean the local town or city building department's inspector: yes absolutely that person can stop a construction project.

But in the case we have been discussing it sounds to me more as if there may have been some confusion about just what the problem is.

How to get along with the building code inspector: comply with the building codes

In my experience, building department officials are sick and tired of people who are trying to evade proper construction codes and practices and not very friendly to people who they think are trying to do something cheap, stupid, or similar.

But excluding a few cases of bad code inspector behavior, if the inspector understands that you want to do what is correct and proper and you fully intend and want to comply with the building codes and officials, you can usually expect the building inspector to be "on your side" and even to help you out by making clear exactly what they think is required.

If then you think what the inspector has said makes no sense, you need to get the requirement clarified; on occasion the building inspector may agree to a variation from what she or he has specified if the variation in turn has been signed-off-on by a licensed building professional such as an architect or engineer. In that case they are passing responsibility for correctness and safety on to that person.

See our definition of building dry in or dry box status in the article above, beginning at BUILDING DRY-IN.

Frankly I cannot imagine that a knowledgeable building professional would want the (insulation and) drywall installed before the building exterior shell is dry - which would normally include the steps I described above. Installing drywall presumes that we have already installed wiring, plumbing, and building insulation first. If those were installed before the building exterior were fully sealed against the weather we are inviting a catastrophe: leaks into the building walls, wet insulation, mold, rot, insects, a disaster.

That's why I said earlier I thought there must be a misunderstanding. In general in construction we frame the structure, then install roof sheathing and roof covering and wall sheathing, then house wrap, then windows, doors, and exterior trim; When those components are in place it is perfectly fine to install the finish siding outside, even if the walls have not been insulated; In fact the more complete that we make the exterior shell of the building the more we are assured that the building is "dry" - which makes the installation of wiring, plumbing, and then insulation safe - in that we don't want wiring or insulation to be wet.

Watch out: some building departments permit drywall to be installed before the building dry-in has been completed provided that moisture-resistant board (presumably greenboard or cement board) is used on the building interior surfaces. In my OPINION this is very risky - wind-blown rain or any other leaks entering enclosed (and worse, insulated) building wall or ceiling cavities is an engraved invitation to possibly dangerous and certainly costly mold contamination that may not be discovered until later. Such problems can be initiated in as little as 24-48 hours after a wetting event. Longer term problems may ensue such as insect infestation or even rot.

More Reading

Green link shows where you are in this article series.


Frequently Asked Questions (FAQs)

Click to Show or Hide FAQs

Ask a Question or Search InspectApedia

Questions & answers or comments about how to select, install, troubleshoot, & repair vinyl siding.

Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.

Search the InspectApedia website

HTML Comment Box is loading comments...

Technical Reviewers & References

Publisher's Google+ Page by Daniel Friedman

Click to Show or Hide Citations & References