Why do I need groundworks before construction?

Groundworks come first because everything you build sits on the soil and the foundation under it, and if that base moves, the whole structure moves with it. Cracks, leaks, and uneven floors almost always start below grade, not above it. Get the ground and the foundation right before you frame, finish, or add weight, and you save yourself the expensive repairs later.

Here in New Hampshire we work on the repair side of that. We do not pour new foundations or build new homes. What we do is fix the ground-level problems that show up in existing houses, so an addition, a finished basement, or a renovation has something solid to stand on. If you are planning to finish a damp basement or add load on top of an aging foundation, the smart move is to handle the wet and the structural issues first.

Why does the base matter so much? A few reasons.

Water is the first one. When your house was built, the crew dug a hole, set the foundation, then pushed the dirt back in around it. That backfill is looser than the soil that was never touched. It drains slowly and holds water right against your wall. Add a season of NH frost heave and that water-logged soil pushes the wall inward. That is how you end up with a bowing wall, a cracked corner, or a wet floor wall joint. None of that gets better once you frame over it.

The fix for water in a basement is our Forever Dry System. Full-perimeter interior drainage, a sump pump sized at 1/2 hp per 120 feet of drain, a 12-mil wall vapor barrier, and a dehumidifier. It is 100% guaranteed to be dry for life! Typical basement waterproofing runs $3,000 to $30,000. If the wet space is a crawl space instead, that is crawlspace encapsulation, not Forever Dry. It runs $3,000 to $25,000 and uses a 12-mil wall and 20-mil floor vapor barrier with dimpled drainage matting under it.

Structure is the second reason. If a foundation wall is cracking, leaning, or settling, you stabilize it before you load it. We self-perform that work in-house. Crack injection runs $1,000 to $3,000. Carbon-fiber straps to hold a bowing wall run $850 each. A steel power brace runs $1,300 per brace. When a footing is settling, helical or push piers run $2,700 per pier for the first three, then $2,200 per pier after that, and a sagging floor on a tired post gets a lally column at $1,300 to $2,500. A failing sill or beam runs $7,000 to $40,000. Some jobs, like a full foundation-wall rebuild, wall anchors, or steel I-beams, we price after we see it.

Here is where we tell you what you do not need. Not every crack is structural. A thin vertical hairline in a poured wall is often just concrete curing, and it may only need injection to keep water out. You do not need piers for that. We will tell you which bucket your house is in after a free inspection, because guessing wrong in either direction costs you money.

One thing we will steer you away from is digging up your yard to waterproof from the outside. In our field experience that fix tends to fail in about two or three years once the soil settles back. The durable fix is interior drainage that manages the water for the life of the house.

What drives the cost? Mostly the size of the area, how much water is coming in, and what the structure needs. A dry crawl with a small footprint is one number. A long basement perimeter with a bowing wall and a settled footing is another. The free inspection is how we sort that out, and you get a written quote within 24 hours.

A little local framing. New England houses settle, soils stay wet, and winters move the ground. That is normal, not a crisis. The goal is to get the base solid once, with a warranty behind it, so the work you do on top lasts.

Want to know what your ground needs first? Call us at 603-610-1770 or book your free inspection. Free inspection, free estimate, written quote within 24 hours.

Helpful internal links: basement waterproofing, crawl space services, structural and foundation repair, foundation repair, helical piers, sill replacement, supplemental support, and the 603 guarantee.

For neutral building-science background, the U.S. Department of Energy’s Building America program covers foundation moisture and insulation at basc.pnnl.gov, and the Insurance Information Institute covers water and structural damage at iii.org.

Related questions

Do I need to fix a wall crack before I finish my basement? Often yes, at least for water. A crack that lets water in will ruin new framing and drywall, so seal it first. Crack injection runs $1,000 to $3,000. If the wall is also bowing, carbon-fiber straps at $850 each hold it before you cover it up.

Is groundworks the same as a new foundation? No. We do not pour new foundations or build new homes. We repair and stabilize the foundations and soil conditions on existing houses, so what you build or finish on top has a solid base.

Should I waterproof from the outside before building? We do not recommend it. Exterior excavation waterproofing tends to fail in about two or three years in our experience. Interior drainage with the Forever Dry System is the durable fix, and basement waterproofing runs $3,000 to $30,000.

How fast can you tell me what my foundation needs? We do a free inspection, then send a written quote within 24 hours. Financing is available through Hearth, subject to approval, and we make nothing on it.