Water Management for New Home Construction in New England

One feature we're particularly proud of in our Smithfield, RI project is the water management system we've incorporated. Water management for new home construction in New England is important for quality and longevity of the home. This build posed three main water management challenges: its waterfront location, New England's unique geography, and the home's modern design. Below is an overview of how we tackled these obstacles and prioritized water management in this new construction.

The Smithfield property sits beside a reservoir, creating challenges due to its geography. Waterfront properties typically face higher moisture levels, stronger winds, significant temperature and humidity fluctuations, and other unpredictable conditions. Additionally, the house is located at the bottom of a valley, which results in severe wind events and heavy rainfall. Without proper sealing and water management, these elements can lead to serious issues.

Smithfield, RI, is part of New England, an area known for its extreme seasons. This adds another layer of complexity in designing an effective water management system. Homes in this region must be built to withstand severe storms, including wind-driven rain, hurricane-force winds, and rapidly changing conditions like snow, hail, and freezing rain. New England's storms can produce several inches of rain or snow in just an hour, and rain, in particular, can be especially challenging as it falls relentlessly. If a building's water management system isn't designed to shed water efficiently, it could result in system failure and water intrusion. Wet building materials are problematic, especially when there’s no way for them to dry out. Today’s homes are often designed to be airtight, with the expectation that they won't get wet—but the key is building homes that don’t allow moisture to penetrate. If done right, there’s no need for a home to "breathe" naturally. Any ventilation should come from mechanical systems, such as HRV or ERV, which ensure proper air exchanges inside the home.

The third consideration when designing the water management system was the home’s specific design. The lack of overhangs or soffits posed a challenge, as these features typically help shield critical areas of the home from the elements. In the absence of these design elements, we needed to plan for the worst-case scenario. This meant preparing for 100- or even 200-year storm events, ensuring that the home’s doors, windows, and assemblies would remain leak-free and structurally sound no matter the conditions.

Here are some of the features and technologies we implemented to address these challenges.

• Benjamin Obdyke Hydrogap SA House Wrap for water management, along with Obdyke Hydrogap LA Liquid-Applied Flashing and Obdyke Hydroflash UV Tape. This is a housewrap that goes over our Zip R9 Sheathing to completely seal and isolate the zip sheathing from being its only "WRB" weather resistant barrier level that protects the outside from the inside. Zip sheathing is rated as being a WRB but we felt it necessary to add another step to it because this home didn't have any overhangs or soffits to give us the extra water protection

  
  
  
  

• Handmade copper pans for all doors and windows. We chose copper because of its life span,

  durability and its ease of workability. This allows for the very slight chance that anything got past our 9 layer approach of house wrap and water management that it would hit the pans and run out, not allowing any water to sit and pool and allow rot to start on the sills. 

  
  

• Rigid black mesh siding rain screen barrier for added durability.-This goes on top of the Obdyke Hydrogap SA house wrap and is the layer that the siding sits up against. It does 2 jobs. First it provides a rigid back material to minimize oil canning and deflection of panels as they warm and cool. And secondly, if any water got behind the siding, it creates a channel for the water to travel down and out from and it creates an air channel for the sheathing wrapped in Hydrogap SA to breathe as the water dissipates down and out of the assembly.

  
  

• Prefa Metals hand-rolled, double-lock standing seam siding and roofing.This is our exterior siding and roofing material which is our first stop of defense in keeping the elements out!

  
  

• Zip System R9 Insulated Sheathing for enhanced insulation. This is exterior sheathing with an R9 value of insulation added to the back of it. The zip sheathing panels are rated as a WRB but we took it a step further to make it even better and more bullet proof. 

  
  

• Custom fascia trim made from LSL-treated lumber with a 45-degree bevel edge, designed to complement the roofline.This is to create solid blocking for our gutter application and also aid in the shedding of water from our roof. 

  
  

• Recessed doors and window sills integrated into the slab, with treated LSL lumber sills fully sealed and waterproofed with Zip liquid flashing. If for some reason water got past our system which is - Metal siding, metal flashing, ridgid rainscreen, hydrogap house wrap SA and fully flashed with liquid flashing all Rough Openings, and then zip sheathing, and then past the copper pans, the actual wooden sills that are in the slab are fully and monolithically sealed that no rot will start to form and occur. A belt and suspenders approach to the extreme. Again, this house has no soffits or overhangs so we must plan for the worst case scenario especially in New England where we have some of the craziest weather in all of the world. 

  
  

Handmade copper pans for all doors