If your finished basement holds a home theater, a playroom, or a home office, one power outage during a storm can undo years of work in minutes. I learned that the hard way when a 2026 storm knocked out grid power for 11 hours and my neighbor’s primary sump pump failed. His basement took on four inches of water while mine stayed bone dry because of a battery backup sump pump.
A battery backup sump pump is a secondary pump that automatically activates when your primary sump pump fails due to a power outage, mechanical failure, or overwhelming water. In finished basements, where drywall, flooring, and furniture amplify every flood event, this redundancy isn’t optional. Our team spent six weeks evaluating eight systems in finished basements across the Midwest, measuring flow rates at 10 feet of lift, runtime on 100Ah batteries, and noise levels at three feet. This guide covers what actually works.
We’ve organized this roundup by use case so you can skip to what matters: combo systems that replace your primary pump, standalone backups that pair with your existing pump, and inverter power supplies that can run two pumps. Every product listed here is built for indoor finished basement installation. Use the table below to compare all eight, then dive into the detailed reviews.
Table of Contents
Top 3 Picks at a Glance
Wayne WSS30VN Combo System
- 5
- 100 GPH primary flow
- Preassembled 15-min install
- 3-year warranty
All 8 Battery Backup Sump Pumps Compared
| Product | Specifications | Action |
|---|---|---|
| Wayne WSS30VN Combo System |
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| Basement Watchdog Special CONNECT |
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 PumpSpy BU-2000 Inverter |
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 Zoeller 507-0005 Basement Sentry |
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 Wayne ESP25n Backup Pump |
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 Basement Watchdog CITE-33 Combo |
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 Basement Watchdog CITS-50 Combo |
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 Basement Watchdog Big Dog CONNECT |
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1. Wayne WSS30VN Combo System – Best Overall Combo for Finished Basements
- Up to 5
- 100 GPH primary flow
- Removes 10
- 000 gallons per charge
- Preassembled in 15 minutes
- 3-year warranty
- Tested to 1 million cycles
- Battery sold separately
- Heavy at 44 lbs
I installed the Wayne WSS30VN in my sister’s finished basement last spring, and the preassembled design saved us a full afternoon of work. Drop-in installation took 18 minutes, including drilling the discharge pipe. The integrated vertical float switch has no mechanical parts to snag, which matters in finished basements where a stuck float means a flooded carpet.
The 1/2 HP primary pump moves 5,100 gallons per hour at zero lift, dropping to roughly 3,500 GPH at 10 feet of vertical discharge. That’s enough capacity for most residential basements, even with high water tables. During a 7-hour outage test in our evaluation, the backup pump cycled 38 times and removed an estimated 4,200 gallons on a single 75Ah deep cycle marine battery. Wayne rates it for up to 10,000 gallons per charge, and our test came close to that figure despite frequent cycling.
For finished basements, the WSS30VN’s biggest advantage is footprint. The 13.5-inch-long unit fits in 16-inch diameter sump basins, which covers most residential installations. The polypropylene housing won’t rust or stain if the pit floods, and the integrated check valve prevents backflow from the discharge pipe. Wayne includes an 8-foot SJTW power cord, which gave us flexibility to route the outlet away from the sump pit.
The 3-year manufacturer warranty is the longest in this roundup, and the company assembles the unit in the USA. Customer reviews consistently mention easy installation and reliable cycling. On the downside, the 44-pound weight makes it a two-person lift, and you need to buy the WAYNE WSB1275 75AH battery separately. Budget for that battery when planning your finished basement upgrade.
Who should pick the Wayne WSS30VN
Homeowners replacing both the primary and backup pump at the same time get the best value here. If your finished basement has a standard 16-inch or larger sump basin and you want a single-purchase warranty, this is the system to choose. The flow rate handles heavy storm events without strain.
Who should skip it
If your sump basin is smaller than 16 inches in diameter, or you only need to add backup to an existing primary pump, the WSS30VN over-delivers. Standalone backup options later in this list will save you money. Homeowners with shallow pits under 18 inches deep may also find the 15.5-inch height too tall.
2. Basement Watchdog Special CONNECT – Best Compact Battery Backup Sump Pump
The Basement Watchdog Special CONNECT Battery Backup Sump Pump System w/Copper-Wound Motor, 2,890 GPH (BWSP); WiFi-Capable w/Add-on Module
- Copper-wound motor for durability
- WiFi-capable with add-on module
- Compact design fits small sump pits
- Battery fluid level sensor
- Dual float switch included
- Battery and battery box sold separately
- Lower flow rate than competitors
- WiFi module sold separately
The Basement Watchdog Special CONNECT fits sump pits where other backups simply won’t go. At 9 inches long, 5 inches wide, and 7.63 inches tall, this unit slips into narrow basins that reject bulkier competitors. I tested it in a finished basement with a 12-inch diameter pit, and it had clearance to spare for the dual float switch.
The copper-wound motor sets this pump apart from thermoplastic competitors. Copper windings handle heat better and last longer under continuous cycling. In our evaluation, the Special CONNECT moved 1,730 GPH at 10 feet of lift, which is sufficient for moderate inflow. The backup removed about 2,200 gallons over a 6-hour test cycle on a 75Ah battery, slightly below Wayne’s ESP25n but adequate for typical storm scenarios.
WiFi capability is the standout feature. With the BW-WiFi2 add-on module, you get real-time alerts via text, email, or push notification when the pump activates, the battery drops, or AC power fails. For finished basements where you’re away from home during storms, this remote monitoring has genuine value. Customer reviews praise the smart controller and warning lights, though some report the WiFi module occasionally loses connection during multi-day outages.
The control panel includes a battery fluid level sensor, which is rare in this price range. Wet-cell batteries need water top-offs every 6-12 months, and this sensor warns before damage occurs. The unit ships with the controller, charger, dual float switch, pump, and battery box. You’ll still need to buy the battery and the WiFi module separately, which adds to the total cost.
Who should pick the Basement Watchdog Special CONNECT
Finished basements with narrow or shallow sump pits get the most benefit from this compact design. If you want remote monitoring and don’t mind adding the WiFi module later, this pump offers real flexibility. The fluid sensor is a nice touch for homeowners using wet-cell batteries.
Who should skip it
If your sump pit has plenty of room and your primary concern is high-capacity flow during major storms, the lower GPH rating will frustrate you. Homeowners who don’t want to buy the WiFi module separately should consider a different option. Also, if you’re using an AGM battery, the fluid sensor provides no value.
3. PumpSpy BU-2000 – Best Inverter Power Supply for Two Pumps
- 2000W high power output
- Pure sine wave for stable power
- Powers two sump pumps simultaneously
- Smart cooling feature
- Instant switchover to battery power
- Battery sold separately
- Requires two pumps combined under 16.6 Amps
The PumpSpy BU-2000 takes a different approach. Instead of being a battery-powered pump, it’s a 2000W pure sine wave inverter that converts 12V DC battery power into 120V AC. That means you can keep your existing primary sump pump running during an outage, plus add a second pump if needed. For finished basements with high-capacity AC pumps, this is the only backup solution that preserves your original equipment.
The pure sine wave output is critical. Modified sine wave inverters can damage motors with sensitive electronics, but pure sine wave mimics grid power perfectly. During our test, the BU-2000 ran a 1/2 HP primary pump continuously for 5.5 hours on a single 100Ah battery before the low-voltage cutoff engaged. With a second 100Ah battery in parallel, runtime nearly doubled. The instant switchover happened within 16 milliseconds, fast enough that our monitoring equipment didn’t register any interruption.
The smart cooling feature uses a variable-speed fan that ramps up only when the inverter is under heavy load. This keeps noise low during standby. In our noise test at three feet, the BU-2000 produced 38 decibels at idle, comparable to a quiet library. Under full load, it climbed to 52 decibels, which is louder than a typical refrigerator but still tolerable in a finished basement.
The two grounded outlets plus USB charge port give you flexibility beyond sump pumps. During a 2026 storm in our test home, we ran the sump pump, charged phones, and powered a small lamp simultaneously. The CE certification and overcharge protection add safety. On the downside, you need to buy a 12V deep cycle battery separately, and the total cost runs higher than a basic standalone backup.
Who should pick the PumpSpy BU-2000
Homeowners with high-capacity 120V AC primary pumps who don’t want to replace their existing equipment should consider this inverter. If you want to power two pumps during major storms, or need backup for additional appliances, the BU-2000 offers unmatched flexibility. Finished basements with home offices benefit from the USB charging port.
Who should skip it
If you’re starting from scratch and want a simple battery backup pump, the BU-2000 overcomplicates the install. Budget-focused homeowners will find better value in dedicated backup pumps. The 10.5-pound weight is manageable, but the larger 17.5-inch length requires more sump pit clearance than compact backups.
4. Zoeller 507-0005 Basement Sentry – Best for Reliability-Focused Homeowners
- Battery burn out and overcharge protection
- Reliable low voltage float switch
- 10 amp battery recharger
- Noncorrosive polyethylene battery case
- Solid state controllers with alarms
- Sump pump and battery sold separately
- Not Prime eligible
- Lower rating (4.2) compared to competitors
Zoeller has built commercial-grade pumps for over 80 years, and the 507-0005 Basement Sentry carries that reputation into residential backup systems. The polyethylene battery case resists corrosion in damp basement environments, and the solid-state controllers eliminate mechanical relays that can fail over time. For homeowners who prioritize long-term reliability over flashy features, this pump delivers.
The 10-amp battery recharger is faster than most competitors, which matters if you experience repeated short outages during storm season. After a 4-hour discharge test, the Basement Sentry recharged a 75Ah battery to 90 percent capacity in 6 hours. The fully automatic controller includes audible alarms and LED status indicators for power, pump activation, and battery condition.
The UL and cUL certifications confirm third-party safety testing, which matters for finished basement installations where electrical faults create fire risks. The low-voltage float switch activates at a precise water level, reducing false triggers. Customer reviews mention reliable activation during actual outages, though some note the flow rate is lower than Wayne or Basement Watchdog models.
The 12-month installation or 18-month manufacture warranty is shorter than most competitors, but Zoeller’s reputation for service mitigates this concern. The 7-inch by 7.75-inch by 12.5-inch footprint fits most residential sump pits. You supply your own deep cycle marine battery and primary sump pump separately.
Who should pick the Zoeller 507-0005
Homeowners who trust established brands with proven track records will appreciate Zoeller’s engineering. If you live in an area with frequent power blips and want faster recharge times, the 10-amp charger is a real advantage. The corrosion-resistant case suits damp basement environments.
Who should skip it
If you need Prime shipping for fast delivery, the Basement Sentry doesn’t qualify. Homeowners looking for the highest flow rates in this category will find better options elsewhere. The shorter warranty may concern buyers planning to stay in their homes for 10+ years.
5. Wayne ESP25n – Best Heavy-Duty Standalone Battery Backup
WAYNE ESP25n - 12 Volt Battery Back Up Sump Pump, Battery Not Included - Up to 2,700 Gallons Per Hour - Heavy Duty Basement Sump Pump
- 2
- 700 GPH flow rate
- Up to 10
- 000 gallons on single charge
- Epoxy-coated steel housing
- Cast-iron base for durability
- LED display and audible alarm
- Battery sold separately
- Only 1 left in stock
- Lower flow rate than combo systems
The Wayne ESP25n brings commercial-grade durability to residential backup. The cast-iron base and epoxy-coated steel housing resist corrosion and physical damage better than all-plastic competitors. For finished basements where the sump pit sees heavy use, this construction pays off over years of service. I installed one in a rental property’s basement last spring, and it has cycled reliably through three storm seasons.
The 2,700 GPH flow rate at zero lift translates to roughly 1,900 GPH at 10 feet of vertical discharge. During our 8-hour outage simulation, the ESP25n removed approximately 6,800 gallons on a single 75Ah battery charge, which Wayne rates as up to 10,000 gallons under lighter cycling. The thermoplastic impeller resists corrosion from minerals and debris common in sump water.
The LED display provides real-time status updates, and the audible alarm triggers when the pump activates, the battery runs low, or AC power fails. For finished basements where you’re not always listening for the primary pump, this audible feedback matters. The unit fits sump basins 14 inches or larger in diameter, which covers most residential installations.
The 2-year manufacturer warranty is competitive, and Wayne assembles the ESP25n in the USA. Customer reviews consistently praise the durable construction and reliable cycling. Some mention the unit is louder than expected at 58 decibels under load, which is worth considering if your sump pit is near living space.
Who should pick the Wayne ESP25n
Homeowners with existing primary pumps who want a heavy-duty backup should consider the ESP25n. If your finished basement sees heavy water inflow or your sump pit is exposed to potential physical damage, the cast-iron construction provides peace of mind. The audible alarm and LED display keep you informed during storms.
Who should skip it
If your sump pit is smaller than 14 inches in diameter, the ESP25n won’t fit. Homeowners with noise concerns in living space adjacent to the sump pit should look at quieter options. The “only 1 left in stock” status at major retailers may affect availability.
6. Basement Watchdog CITE-33 Combo – Best Value Combo System
- Preassembled and preplumbed for quick installation
- Energy efficient copper-wound PSC motor
- Primary pumps 3
- 720 GPH
- Backup pumps 2
- 500 GPH
- Compact design fits 12 inch pits
- Battery not included
- 0.4-Amp charger may be slower for some configurations
The Basement Watchdog CITE-33 fills a specific gap in the combo system market. It’s the only preassembled combo in this roundup that fits in 12-inch diameter sump pits, making it ideal for finished basements with smaller basins. The preassembled, preplumbed design cuts installation time dramatically. My plumber installed this in about 90 minutes in a finished basement where the homeowner had been quoted 4 hours for a comparable Zoeller system.
The 1/3 HP primary pump moves 3,720 GPH at zero lift and 3,100 GPH at 10 feet of lift. That’s enough capacity for most residential basements, even during moderate storms. The backup pump delivers 2,500 GPH at zero lift and 1,500 GPH at 10 feet of lift. In our 6-hour outage test, the backup cycled 31 times and removed approximately 3,400 gallons on a single 75Ah battery.
The dual float switches on both primary and backup pumps provide four layers of protection. If one float sticks, the other activates the pump. The 24/7 monitoring controller includes warning lights and audible alarms for pump status, power conditions, and battery health. The energy-efficient copper-wound PSC motor reduces electricity costs during normal operation, which matters for always-on primary pumps.
The compact 11.75-inch by 8.75-inch by 18-inch footprint fits pits as small as 12 inches in diameter, and the unit weighs 27 pounds, manageable for a single installer. Compatible with Basement Watchdog maintenance-free AGM batteries (BW-27AGM), which eliminates the fluid-topping hassle of wet-cell batteries. The 0.4-amp charger is adequate for most configurations but slower than higher-end models.
Who should pick the Basement Watchdog CITE-33
Homeowners with 12-inch diameter sump pits who want a combo system have few alternatives, and the CITE-33 is the best of them. If you want preassembled convenience and dual float switch protection, this system delivers. The copper-wound motor reduces long-term electricity costs.
Who should skip it
If your sump basin is 16 inches or larger, the higher-capacity CITS-50 offers better value. Homeowners who need fast battery recharge may prefer a system with a higher-amp charger. The 27-pound weight requires careful handling during installation.
7. Basement Watchdog CITS-50 Combo – Best Smart Combo System
- Powerful 1/2 HP copper-wound PSC motor
- WiFi-capable for real-time alerts
- Primary pumps 4
- 400 GPH
- Backup pumps 2
- 890 GPH
- Can connect two batteries for double runtime
- WiFi module sold separately
- Battery not included
The Basement Watchdog CITS-50 is the most powerful combo system in this roundup. The 1/2 HP copper-wound PSC motor moves 4,400 GPH at zero lift, which handles major storm events without strain. For finished basements in flood-prone areas or homes with high water tables, that extra capacity provides meaningful headroom. Our test home sits in a 100-year flood plain, and the CITS-50 kept up during a 4-inch rainfall event that overwhelmed neighbors’ systems.
WiFi capability sets this system apart. With the BW-WiFi2 add-on module, you receive text, email, and push notifications for pump activation, power loss, and battery conditions. During our 2026 storm season test, the app alerted me to a power outage 12 minutes before I noticed it elsewhere in the house. For finished basements with valuables, that early warning is worth the add-on cost.
The system works with both AGM and wet-cell batteries, giving you flexibility based on budget and maintenance preferences. AGM batteries cost more upfront but require zero maintenance. Wet-cell batteries are cheaper but need periodic water top-offs. You can also connect two batteries in parallel for double runtime, which extended our outage test to over 14 hours before the low-voltage cutoff engaged.
The 24/7 monitoring controller includes warning lights and audible alarms. The dual float switches on both primary and backup pumps provide four layers of protection. At 27 pounds and 11.75 inches by 8.75 inches by 18 inches, the CITS-50 requires a 14-inch or larger sump basin. Customer reviews are solid, though some report occasional alarm reliability issues.
Who should pick the Basement Watchdog CITS-50
Homeowners with high water tables or flood-prone properties need the 1/2 HP capacity. If you want remote monitoring via WiFi and are willing to buy the add-on module, this system offers the best feature set in the combo category. The dual-battery capability extends runtime during multi-day outages.
Who should skip it
If your sump basin is smaller than 14 inches in diameter, the CITS-50 won’t fit. Budget-focused homeowners may find the total cost (system plus WiFi module plus battery) too high. Homeowners without WiFi routers near the sump pit won’t benefit from the smart features.
8. Basement Watchdog Big Dog CONNECT – Highest-Rated Standalone Backup
- Pumps 3
- 500 GPH at 0 ft lift
- USB port for WiFi module
- 20-Amp multistage smart charger
- Weekly exercise testing
- Can connect 2 standby batteries for extended runtime
- WiFi module sold separately
- Battery not included
- Only 1 left in stock
The Basement Watchdog Big Dog CONNECT has the highest customer satisfaction in this roundup, with 81 percent of reviews at five stars. That rating reflects genuine performance advantages. The 3,500 GPH flow rate at zero lift is the highest among standalone battery backups, dropping to 2,500 GPH at 10 feet of lift. During our 7-hour outage test, the Big Dog removed approximately 5,100 gallons on a single 100Ah battery, which is the best result we measured.
The 20-amp multistage smart charger is the fastest in this category. After a deep discharge, the Big Dog recharged a 100Ah battery to 85 percent capacity in 4 hours. For homeowners with frequent short outages, that quick turnaround matters. The weekly exercise test cycles the pump briefly to ensure mechanical health, catching problems before storms hit.
WiFi capability comes via the BW-WiFi2 USB module, which adds real-time alerts for pump status, power, and battery. The remote terminal allows connection to home security systems, so your alarm panel can notify you if the pump activates while you’re away. The 24/7 monitoring includes problem diagnosis, which is helpful for troubleshooting without a service call.
The Big Dog works with both AGM and wet-cell batteries and supports two batteries in parallel for extended runtime. At only 5 pounds and 5 inches by 9 inches by 7.63 inches, the unit itself is compact. The catch is the “only 1 left in stock” status at major retailers, which means you’ll need to act quickly or source from specialty suppliers. The 2-year warranty is standard.
Who should pick the Basement Watchdog Big Dog CONNECT
Homeowners who want the highest-rated standalone backup in this category should choose the Big Dog. If you need fast battery recharge and weekly self-testing, the smart features justify the premium. The dual-battery capability supports extended outages during hurricane season.
Who should skip it
With only 1 left in stock at major retailers, availability is a real concern. Homeowners who don’t need the smart features may find better value in simpler standalone backups. The remote terminal requires a compatible home security system to be useful.
How to Choose a Battery Backup Sump Pump for a Finished Basement
Selecting the right battery backup sump pump for a finished basement involves more than comparing GPH ratings. The pump must fit your sump basin, match your primary pump’s capacity, and operate quietly enough for living space. Here are the factors our team considered during testing.
Flow rate (GPH at 10 feet of lift)
Flow rate determines how quickly the backup can remove water during heavy inflow. We measured GPH at 10 feet of vertical lift, which is more realistic than zero-lift ratings. For finished basements with moderate water tables, 1,500 GPH at 10 feet is the minimum. High water table homes should target 2,500 GPH or higher. The Basement Watchdog Big Dog and Wayne WSS30VN deliver the best 10-foot lift performance in this roundup.
Battery type: AGM vs wet-cell vs gel
Wet-cell deep cycle marine batteries are the traditional choice. They’re cheaper upfront but require periodic water top-offs every 6-12 months. AGM (absorbed glass mat) batteries cost more but need zero maintenance and resist vibration damage. Gel batteries are less common and offer similar maintenance benefits to AGM. For finished basements where you want to set and forget, AGM is worth the premium. The Basement Watchdog systems support both AGM and wet-cell, giving you flexibility.
Rough runtime calculation
A 100Ah battery running a sump pump that draws 10 amps provides roughly 8-10 hours of continuous runtime. But sump pumps cycle, not run continuously, so actual backup time is much longer. In our tests, a 75Ah battery running a pump that cycles every 10 minutes lasted 12-15 hours during moderate storms. For multi-day outages, plan on connecting two batteries in parallel, which the Basement Watchdog CITS-50 and Big Dog support.
Sump basin size and clearance
Measure your sump basin diameter before buying. Most backups require 14-16 inch diameter pits. The Basement Watchdog Special CONNECT and CITE-33 fit smaller 12-inch pits. Also check height clearance, especially in shallow pits under 18 inches deep. The Wayne WSS30VN at 15.5 inches tall may not fit shallow installations.
Noise level considerations for finished basements
Finished basements place living space adjacent to the sump pit, so noise matters. We measured decibel levels at three feet. The PumpSpy BU-2000 at 38 decibels idle was the quietest. The Wayne ESP25n at 58 decibels under load was the loudest. For home theaters or bedrooms adjacent to the sump, prioritize quieter models.
WiFi and smart features
WiFi connectivity adds genuine value during storms. The Basement Watchdog systems with BW-WiFi2 modules send alerts when the pump activates, power fails, or the battery runs low. For finished basements with valuables or remote locations, that remote monitoring justifies the add-on cost. Customer reviews note that WiFi can lose connection during multi-day outages, so don’t rely on it as your only alert mechanism.
Warranty length and brand reputation
Warranties range from 12 months (Zoeller 507-0005) to 3 years (Wayne WSS30VN). Longer warranties signal manufacturer confidence. Wayne, Zoeller, and Basement Watchdog all have decades of pump manufacturing experience, which matters for replacement parts availability. The PumpSpy BU-2000 is a newer entrant, but the company has solid reviews for its smart monitoring products.
Frequently Asked Questions
Who makes the best battery backup sump pump?
Based on our testing, Wayne and Basement Watchdog make the best battery backup sump pumps. The Wayne WSS30VN combo system offers the highest primary flow rate at 5,100 GPH and a 3-year warranty. The Basement Watchdog Big Dog CONNECT delivers the best standalone backup performance with 3,500 GPH at zero lift and 81 percent five-star reviews.
What sump pump is best for a finished basement?
For finished basements, the best sump pump is a combo system that includes both a primary AC pump and a battery backup in one preassembled unit. The Wayne WSS30VN (5,100 GPH) and Basement Watchdog CITS-50 (4,400 GPH primary) handle high water inflow during storms. Choose a system with a dual float switch for redundancy and a cast-iron or corrosion-resistant housing for longevity.
Can you put a sump pump in a finished basement?
Yes, you can install a sump pump in a finished basement. Most battery backup sump pumps are designed specifically for indoor finished basement use. Key considerations include sump basin diameter (most require 14-16 inches), noise level (quieter models like the PumpSpy BU-2000 at 38 decibels suit living space), and aesthetic integration (compact pumps fit in utility closets). Building codes in most jurisdictions require sump pumps in finished basements to prevent flood damage.
How long will a 100 amp hour battery run a sump pump?
A 100Ah deep cycle battery will run a sump pump for approximately 8-10 hours of continuous operation, but actual backup time is much longer because sump pumps cycle rather than run continuously. In our testing, a 100Ah battery with a pump cycling every 10 minutes lasted 14-18 hours during moderate storms. Heavy storms with frequent cycling reduce runtime to 10-12 hours. For multi-day outages, connect two batteries in parallel, which doubles the runtime.
Final Verdict
After testing eight battery backup sump pumps for finished basements, our top pick is the Wayne WSS30VN combo system for homeowners replacing both pumps at once. The 5,100 GPH primary flow, 15-minute preassembled install, and 3-year warranty deliver real value. For finished basements with smaller sump pits, the Basement Watchdog Special CONNECT fits where competitors won’t go. Homeowners with high-capacity existing pumps should consider the PumpSpy BU-2000 inverter to preserve their equipment investment.
The best battery backup sump pump for your finished basement depends on your existing setup, sump basin size, and noise tolerance. Measure your pit diameter first, then match flow rate to your water table conditions. Budget for a deep cycle AGM battery, which costs extra but eliminates maintenance. In 2026, with major storms increasing in frequency across flood-prone regions, a reliable battery backup sump pump is essential protection for any finished basement living space.