Price What Connects the Austin ADU to the Property

A useful site budget begins with a marked-up plan and a list of known facts. It does not begin with a generic “utility allowance.”

Find every company and connection

Record the electric, water and wastewater companies for the address. Austin Energy and Austin Water serve many properties. But not every property using an Austin mailing address. Some areas involve city utility districts, other utilities or onsite wastewater.

List meter details, visible services, available plans and utility-company contacts. Clearly mark anything that still needs to be checked.

Draw the current-service map

On the site plan, show:

• electric service, meter, panels and overhead/underground routes.
• water meter, service entry and likely private branches.
• wastewater cleanouts, building drain and available elevation details.
• septic components where applicable.
• communications.
• stormwater flow and roof discharge.
• trees, easements, paving and retaining work.
• the planned building route.

Use locating, survey or field review where records do not confirm the needed position.

Calculate electrical demand

The ADU may add electric cooking, water heating, cooling, outlets and vehicle charging. Have a qualified expert record the current service and calculate the new demand. Decide where the panel, meter, trench and conduit will go. Include any needed work at the main house.

Ask whether the estimate includes utility work and repairs to the yard or house. Another owner’s costly transformer or service change is a reason to check your property. It is not a standard Austin price.

Plan water from meter to fixtures

Confirm the connection, pipe route, pipe size, protection and shutoffs. Show any work needed inside the current home. Check the utility company’s filing and meter rules, and state who pays each charge.

Coordinate the water design with trees, paving and wastewater trenches. The shortest line may not create the least property disruption.

Establish the wastewater elevation

Gravity drainage depends on measured heights. Record the ADU floor and fixture levels, connection point, route, slope, cleanouts and trench depth. If gravity will not work, require another designed solution. State who will own and maintain it.

For garage conversions, compare the desired floor with existing slab and sewer levels. For rear-yard units, price distance, access and repairs after the work. Do not assume an existing house connection has unlimited capacity.

Coordinate drainage and impervious cover

Show the new roof, paths, driveway changes and other hard surfaces. Explain where rainwater will go and how the final grade protects both homes and nearby properties. Check the current Austin rules, including any HOME or infill rules for the site.

Temporary controls also matter. Define protection of exposed soil, excavations and stored material during heavy rain.

Protect trees during permanent and temporary work

Map tree trunks, canopies and important root areas. Add the foundation, trenches, equipment paths, material storage and grade changes. Construction can harm a tree even when the final wall is outside the protected area.

Obtain qualified tree input where needed and put protection details in the building package. Enforce them before machinery arrives.

Measure access and repairs after construction

Record gate and side-yard width, slopes, overhead lines, steps and vehicle staging. Decide how excavation, concrete, framing and waste move through the site.

List everything likely to be disturbed, including paving, decks, fences, gates, irrigation, lawns, plants and indoor finishes. State the expected repair quality. Photograph each area before work begins.

Price four layers for each service

Divide each utility cost into:

1. Review and design.
2. Company or agency fees.
3. Building and connection.
4. Removal and reinstatement.

Label each amount as fixed, based on quantity, an allowance or paid directly by the owner. If a condition is still unknown, state how the final price will be calculated.

Keep an unknowns ledger

For each open site question, record the current assumption and the facts still needed. Assign one person and a due date. Explain the possible cost or schedule effect. Resolve major unknowns before signing a fixed construction price when possible.

The Austin cost guide integrates this ledger with the owner forecast.

Price the access route as temporary infrastructure

Show how workers, digging equipment and materials will reach the unit. Include temporary fence removal, ground protection, neighbor notice and soil removal. List the surfaces that will need repair.

If the price assumes a crane, pump or small machine, state the needed work area and access width. If the site cannot provide that access, change the building method and budget.

Coordinate drainage with the finished yard

New roof and paving change runoff. Draw roof discharge, grading, swales and any required controls with the final landscaping. Do not leave drainage as an undefined site allowance after foundation design.

Record who designs the drainage, checks site heights and repairs damaged irrigation or plants. Give the owner the final drainage plan with the approval records.

Keep service work on the main schedule

Utility filings, inspections, outages and meter work may sit outside the general contractor’s direct control. Add them as named activities with owners, prerequisites and status dates.

Start slow utility-company work once the approved concept is stable. Do not wait until indoor plumbing or electrical work depends on it.